version 5.1.16

- threshold.py: add _find_threshold() with suffix fallback so thresholds
  like ping_monitor.rtt_avg match ping_monitor.8_8_8_8_rtt_avg etc.;
  each pinged host keeps its own alert state
- hbdclass.py: format RTT as integer ms (round())
- live.html: JS RTT display rounded to nearest ms (Math.round)

Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>

CLAUDE. md

@@ -0,0 +1,4 @@
+1. Don't assume. Don't hide confusion. Surface tradeoffs.
+2. Minimum code that solves the problem. Nothing speculative.
+3. Touch only what you must. Clean up only your own mess.
+4. Define success criteria. Loop until verified.

README.md

@@ -267,6 +267,41 @@ All plugin metrics can be thresholded:
 - **Network**: errors_total, dropped packets, connection counts
 - **Nagios**: exit_code mapping (0=OK, 1=WARNING, 2=CRITICAL)
 
+### Per-Host Threshold Profiles
+
+Named threshold configurations let different hosts use different limits. A host's `threshold_config` can be a single name or a **list** — lists are applied left-to-right so profiles compose without duplication:
+
+```yaml
+threshold_configs:
+  default:
+    thresholds:
+      cpu_monitor:
+        cpu_percent: {warning: 80, critical: 90}
+      memory_monitor:
+        memory_percent: {warning: 85, critical: 95}
+
+  tight_cpu:           # override CPU limits only
+    thresholds:
+      cpu_monitor:
+        cpu_percent: {warning: 60, critical: 75}
+
+  db_disk:             # add a database partition check
+    thresholds:
+      disk_monitor:
+        partitions:
+          /var/lib/postgresql:
+            percent: {warning: 75, critical: 88}
+
+hosts:
+  web-01:
+    threshold_config: default          # single profile
+
+  db-01:
+    threshold_config: [tight_cpu, db_disk]   # layered: CPU override + extra disk check
+```
+
+Each named config's overrides are applied in order on top of the defaults. Metrics not mentioned in a profile are inherited unchanged.
+
 See [docs/THRESHOLD_ALERTING.md](docs/THRESHOLD_ALERTING.md) for comprehensive documentation including best practices, troubleshooting, and advanced configuration.
 
 ---
@@ -377,7 +412,7 @@ This project now declares its dependencies in `pyproject.toml`. Instead
 of the old `requirements.txt` flow, install the package into a virtualenv
 using `pip`:
 
-See `scripts/install.sh` for a way to install.
+See `scripts/hb_install.sh` for a way to install.
 
 Run the daemon (example):
 
@@ -441,6 +476,68 @@ plugins:
 
 All monitoring plugins default to 5-minute (300 second) intervals, but can be customized as needed.
 
+### hbc_mini — single-file client (no external dependencies)
+
+`scripts/hbc_mini.py` is a self-contained version of the heartbeat client that requires only Python 3.8+ and no external packages. Copy it to any host and run it directly — no virtualenv, no `pip install`.
+
+```bash
+# Basic usage
+python3 hbc_mini.py your-server.example.com
+
+# Run as daemon
+python3 hbc_mini.py -d your-server.example.com
+
+# Send a boot message
+python3 hbc_mini.py -b your-server.example.com
+
+# Send a one-off message
+python3 hbc_mini.py -m "maintenance starting" your-server.example.com
+```
+
+**Config:** `~/.hbc.json` (same keys as `~/.hbc.yaml`, JSON format). Example:
+
+```json
+{
+  "hb_port": 50003,
+  "interval": 30,
+  "plugins": {
+    "ping_monitor": {
+      "interval": 60,
+      "hosts": ["8.8.8.8", "192.168.1.1"]
+    },
+    "nagios_runner": {
+      "interval": 300,
+      "commands": [
+        {"name": "check_load", "command": "/usr/lib/nagios/plugins/check_load -w 5,4,3 -c 10,8,6"}
+      ]
+    }
+  }
+}
+```
+
+**Plugin availability:**
+
+| Plugin | Platform | Data source |
+|---|---|---|
+| `os_info` | all | `platform` stdlib |
+| `ping_monitor` | all | `ping` subprocess |
+| `nagios_runner` | all (not Windows) | subprocess |
+| `cpu_monitor` | Linux | `/proc/stat` |
+| `memory_monitor` | Linux | `/proc/meminfo` |
+| `disk_monitor` | Linux, macOS, BSD | `df -P` subprocess |
+| `network_monitor` | Linux | `/proc/net/dev` |
+
+**What is not available compared to the full `hbc`:**
+
+- No YAML config (use JSON instead)
+- No `filesystem_info` plugin
+- `cpu_monitor` does not report per-core usage or CPU frequency (no psutil)
+- Plugins cannot be loaded from external `.py` files — all plugins are compiled in
+
+Everything else — heartbeat protocol, ACK/CMD/UPD handling, `hb_install.sh`-based self-update, daemonize, syslog — is identical to the full client.
+
+---
+
 ## 🐞 Debugging in VS Code
 
 This repository includes a ready-to-use `.vscode/launch.json` with configurations to run or attach the VS Code debugger to `hbd`.

REFACTORING.md

@@ -1,234 +0,0 @@
-# HBD/HBC Separation Refactoring
-
-## Overview
-
-The heartbeat monitoring system has been refactored into a modular package structure with separate client and server components. This allows users to install only what they need and provides clear separation of concerns.
-
-## New Package Structure
-
-```
-hbd/
-├── __init__.py                 # Main package (minimal)
-├── client/                     # HBC - System monitoring client
-│   ├── __init__.py
-│   ├── main.py                # Entry point (was hbc.py)
-│   ├── config.py              # Client-specific configuration
-│   ├── plugin.py              # Plugin framework
-│   ├── threshold.py           # Threshold checking
-│   └── plugins/               # Monitoring plugins
-│       ├── cpu_monitor.py
-│       ├── disk_monitor.py
-│       ├── memory_monitor.py
-│       ├── network_monitor.py
-│       ├── filesystem_info.py
-│       ├── os_info.py
-│       └── nagios_runner.py
-├── server/                     # HBD - Heartbeat daemon/server
-│   ├── __init__.py
-│   ├── main.py                # Server runtime (was server.py)
-│   ├── cli.py                 # Command-line interface
-│   ├── config.py              # Server-specific configuration
-│   ├── http.py                # HTTP/REST API
-│   ├── ws.py                  # WebSocket server
-│   ├── udp.py                 # UDP heartbeat listener
-│   ├── dns.py                 # DNS update functionality
-│   ├── notify.py              # Notification handlers
-│   ├── monitor.py             # Host monitoring
-│   ├── hbdclass.py            # Host class definitions
-│   ├── journal.py             # Message journaling
-│   ├── templates/             # Jinja2 web templates
-│   └── static/                # Web UI assets
-└── common/                     # Shared utilities
-    ├── __init__.py
-    ├── proto.py               # Protocol encoding/decoding
-    └── utils.py               # Common utilities
-
-## Configuration Files
-
-### Client Configuration (hbd/client/config.py)
-
-Client-specific defaults:
-- `hb_port`: Port where hbd servers listen (default: 50003)
-- `interval`: Heartbeat interval in seconds (default: 10)
-- `plugins`: Per-plugin configuration
-- `thresholds`: Threshold configuration for monitoring
-
-### Server Configuration (hbd/server/config.py)
-
-Server-specific defaults:
-- `hb_port`: Port to listen for heartbeats (default: 50003)
-- `hbd_port`: HTTP API port (default: 50004)
-- `ws_port`: WebSocket port (default: 50005)
-- `logfile`: Log file path
-- `pushsrv`, `pushover_token`, etc.: Notification settings
-- `watchhosts`, `dyndnshosts`: Host monitoring
-- `smtpserver`, etc.: Email settings
-- `journal_*`: Message journaling settings
-
-## Installation Options
-
-### Install Core Only (minimal, PyYAML only)
-```bash
-pip install hbd
-```
-
-### Install Client Only (for monitoring)
-```bash
-pip install hbd[client]
-# Installs: PyYAML, psutil
-```
-
-### Install Server Only (for daemon)
-```bash
-pip install hbd[server]
-# Installs: PyYAML, websockets, mattermostdriver, aiohttp, Jinja2
-```
-
-### Install Everything
-```bash
-pip install hbd[all]
-# Installs all dependencies for both client and server
-```
-
-### Development Installation
-```bash
-pip install -e ".[dev]"
-# Includes all dependencies plus testing/linting tools
-```
-
-## Command-Line Interfaces
-
-### HBC (Client)
-```bash
-hbc [options] host1 [host2 ...]
-
-# Entry point: hbd.client.main:main
-# Location: hbd/client/main.py
-```
-
-### HBD (Server)
-```bash
-hbd [options]
-
-# Entry point: hbd.server.cli:main
-# Location: hbd/server/cli.py → hbd/server/main.py
-```
-
-## Import Changes
-
-### Client Code
-```python
-# Old imports
-from .config import load_config
-from .proto import dicttos, stodict
-from .plugin import PluginRegistry
-
-# New imports
-from .config import load_config          # Still in client/
-from ..common.proto import dicttos       # Moved to common/
-from .plugin import PluginRegistry       # Still in client/
-```
-
-### Server Code
-```python
-# Old imports
-from .config import load_config
-from .proto import stodict
-from .threshold import AlertLevel
-
-# New imports
-from .config import load_config          # Server-specific config
-from ..common.proto import stodict       # Moved to common/
-from ..client.threshold import AlertLevel # Client module
-```
-
-### Plugin Code
-```python
-# Old import
-from hbd.plugin import MonitorPlugin
-
-# New import
-from hbd.client.plugin import MonitorPlugin
-```
-
-## Benefits
-
-1. **Modular Installation**: Install only what you need
-   - Client-only systems don't need web server dependencies
-   - Server-only systems don't need psutil
-   
-2. **Clearer Architecture**: Explicit separation of concerns
-   - Client: System monitoring and data collection
-   - Server: Heartbeat reception, web UI, notifications
-   - Common: Shared protocol and utilities
-
-3. **Independent Evolution**: Client and server can evolve separately
-   - Different release cycles possible
-   - Clear API boundaries via common/
-
-4. **Smaller Footprint**: Reduced dependency installation
-   - Client: ~1 dependency (psutil)
-   - Server: ~4 dependencies (websockets, aiohttp, Jinja2, mattermostdriver)
-
-## Migration Guide
-
-### For Existing Installations
-
-1. **Reinstall the package**:
-   ```bash
-   pip install -e ".[all]"  # For development
-   # or
-   pip install hbd[all]     # For production
-   ```
-
-2. **Configuration files remain unchanged**:
-   - Both client and server read from `~/.hb.yaml`
-   - All existing config keys are supported in both configs
-   - Server has additional keys (journal, websocket, email, etc.)
-   - Client has minimal keys (interval, plugins, thresholds)
-
-3. **Commands remain the same**:
-   - `hbc` command works identically
-   - `hbd` command works identically
-
-### For New Deployments
-
-1. **Client-only system** (monitoring host):
-   ```bash
-   pip install hbd[client]
-   hbc server1.example.com server2.example.com
-   ```
-
-2. **Server-only system** (monitoring daemon):
-   ```bash
-   pip install hbd[server]
-   hbd -c /etc/hbd.yaml -f
-   ```
-
-3. **Combined system** (dev/test):
-   ```bash
-   pip install hbd[all]
-   ```
-
-## Testing
-
-All imports and entry points have been tested and validated:
-- ✅ Package imports work correctly
-- ✅ `hbc` command entry point functional
-- ✅ `hbd` command entry point functional
-- ✅ Optional dependencies properly configured
-- ✅ All internal imports updated
-
-## Files Archived
-
-The following files were renamed to avoid conflicts:
-- `hbd/config.py` → `hbd/config.py.old` (split into client/server configs)
-- `hbd/hbc_old.py` → `hbd/hbc_old.py.bak` (backup file)
-
-## Next Steps
-
-1. Test client functionality with a monitoring host
-2. Test server functionality with web UI and notifications
-3. Update documentation (README.md) with new structure
-4. Consider publishing to PyPI with new structure
-5. Update any deployment scripts/Dockerfiles to use optional dependencies

docs/THRESHOLD_ALERTING.md

@@ -814,34 +814,32 @@ Planned features:
 
 ## Multi-Threshold Configuration
 
-**New in version 2.0**: Support for multiple named threshold configurations with per-host mapping.
+Support for multiple named threshold configurations with per-host mapping and composable layering.
 
 ### Overview
 
 The multi-threshold feature allows you to:
-- Define multiple sets of threshold configurations
+- Define multiple named threshold configurations
-- Map different hosts to different threshold sets
+- Assign one or more configurations to each host
+- Compose configurations by layering — each named config's overrides are applied in order on top of the defaults
 - Use different sensitivity levels for different environments
-- Maintain a default configuration for unmapped hosts
 
 ### Configuration Structure
 
+Named configurations are defined under `threshold_configs`. Each host selects which ones to use via `threshold_config` in the `hosts` section (a string for a single config, or a list to layer multiple):
+
 ```yaml
-# Optional: Set the default configuration name (defaults to "default")
+# Optional: set the default configuration name (defaults to "default")
 default_threshold_config: "default"
 
-# Define multiple named threshold configurations
 threshold_configs:
-  # Configuration name 1
   default:
     thresholds:
-      # Standard threshold definitions
       cpu_monitor:
         cpu_percent:
           warning: 80.0
           critical: 90.0
 
-  # Configuration name 2
   high_sensitivity:
     thresholds:
       cpu_monitor:
@@ -849,7 +847,6 @@ threshold_configs:
           warning: 60.0
           critical: 75.0
 
-  # Configuration name 3
   low_sensitivity:
     thresholds:
       cpu_monitor:
@@ -857,14 +854,77 @@ threshold_configs:
           warning: 90.0
           critical: 95.0
 
-# Map specific hosts to specific configurations
+hosts:
-host_threshold_mapping:
+  prod-web-01:
-  prod-web-01: high_sensitivity
+    threshold_config: high_sensitivity   # single config
-  prod-web-02: high_sensitivity
+
-  dev-server-01: low_sensitivity
+  dev-server-01:
-  # Unmapped hosts use default_threshold_config
+    threshold_config: low_sensitivity
+
+  # Hosts with no threshold_config use default_threshold_config
 ```
 
+### Composable Configurations (list form)
+
+`threshold_config` can be a list. Configs are applied **left to right**: the defaults are the base, then each named config's overrides are layered on top. Later entries in the list win on any metric they define.
+
+```yaml
+threshold_configs:
+  default:
+    thresholds:
+      cpu_monitor:
+        cpu_percent: {warning: 80, critical: 90}
+      memory_monitor:
+        memory_percent: {warning: 85, critical: 95}
+      disk_monitor:
+        partitions:
+          /:
+            percent: {warning: 80, critical: 90}
+
+  # Tighter CPU limits for busy servers
+  high_cpu_load:
+    thresholds:
+      cpu_monitor:
+        cpu_percent: {warning: 60, critical: 75}
+
+  # Tighter disk limits for data-heavy servers
+  busy_disk:
+    thresholds:
+      disk_monitor:
+        partitions:
+          /:
+            percent: {warning: 70, critical: 85}
+
+hosts:
+  # Gets default thresholds only
+  web-01:
+    threshold_config: default
+
+  # Gets tighter CPU limits, default memory and disk
+  build-server:
+    threshold_config: high_cpu_load
+
+  # Layers both: tighter CPU AND tighter disk, default memory
+  db-01:
+    threshold_config: [high_cpu_load, busy_disk]
+
+  # Three layers: busy_disk overrides high_cpu_load if they conflict
+  storage-01:
+    threshold_config: [default, high_cpu_load, busy_disk]
+```
+
+**How layering works:**
+
+Starting from the `default` thresholds:
+
+| Layer | Applied config | Effect |
+|-------|---------------|--------|
+| Base  | `default` | all default thresholds |
+| +1    | `high_cpu_load` | cpu_percent overridden to 60/75 |
+| +2    | `busy_disk` | disk percent overridden to 70/85; cpu_percent stays at 60/75 |
+
+Each named config only overrides the metrics it explicitly defines. Metrics not mentioned in a config inherit from the layers beneath.
+
 ### Use Cases
 
 #### 1. Environment-Based Thresholds
@@ -887,11 +947,15 @@ threshold_configs:
           warning: 90.0   # More relaxed for dev
           critical: 98.0
 
-host_threshold_mapping:
+hosts:
-  prod-web-01: production
+  prod-web-01:
-  prod-web-02: production
+    threshold_config: production
-  dev-web-01: development
+  prod-web-02:
-  dev-web-02: development
+    threshold_config: production
+  dev-web-01:
+    threshold_config: development
+  dev-web-02:
+    threshold_config: development
 ```
 
 #### 2. Server Role-Based Thresholds
@@ -914,7 +978,7 @@ threshold_configs:
           warning: 70.0
           critical: 85.0
       memory_monitor:
-        percent:
+        memory_percent:
           warning: 90.0   # Databases can use high memory
           critical: 97.0
       disk_monitor:
@@ -927,17 +991,23 @@ threshold_configs:
   cache:
     thresholds:
       memory_monitor:
-        percent:
+        memory_percent:
           warning: 95.0   # Redis/Memcached can use very high memory
           critical: 99.0
 
-host_threshold_mapping:
+hosts:
-  web-01: webserver
+  web-01:
-  web-02: webserver
+    threshold_config: webserver
-  db-01: database
+  web-02:
-  db-02: database
+    threshold_config: webserver
-  redis-01: cache
+  db-01:
-  memcached-01: cache
+    threshold_config: database
+  db-02:
+    threshold_config: database
+  redis-01:
+    threshold_config: cache
+  memcached-01:
+    threshold_config: cache
 ```
 
 #### 3. Sensitivity Levels
@@ -952,7 +1022,7 @@ threshold_configs:
         partitions:
           /:
             percent:
-              warning: 70.0    # Very sensitive
+              warning: 70.0
               critical: 80.0
               hysteresis: 0.15
 
@@ -976,12 +1046,69 @@ threshold_configs:
               critical: 98.0
               hysteresis: 0.05
 
-host_threshold_mapping:
+hosts:
-  payment-gateway: critical
+  payment-gateway:
-  auth-server: critical
+    threshold_config: critical
-  web-01: standard
+  auth-server:
-  web-02: standard
+    threshold_config: critical
-  test-server: relaxed
+  web-01:
+    threshold_config: standard
+  web-02:
+    threshold_config: standard
+  test-server:
+    threshold_config: relaxed
+```
+
+#### 4. Composable Profiles
+
+Build host-specific thresholds by combining small, focused configs:
+
+```yaml
+threshold_configs:
+  # Baseline — everything at default levels
+  default:
+    thresholds:
+      cpu_monitor:
+        cpu_percent: {warning: 80, critical: 90}
+      memory_monitor:
+        memory_percent: {warning: 85, critical: 95}
+
+  # Overlay: tighter CPU only
+  tight_cpu:
+    thresholds:
+      cpu_monitor:
+        cpu_percent: {warning: 60, critical: 75}
+
+  # Overlay: tighter memory only
+  tight_memory:
+    thresholds:
+      memory_monitor:
+        memory_percent: {warning: 70, critical: 85}
+
+  # Overlay: extra disk partition for database servers
+  db_disk:
+    thresholds:
+      disk_monitor:
+        partitions:
+          /var/lib/postgresql:
+            percent: {warning: 75, critical: 88}
+
+hosts:
+  # Plain web server
+  web-01:
+    threshold_config: default
+
+  # Build server: tight CPU, default memory and disk
+  build-01:
+    threshold_config: tight_cpu
+
+  # Database: tight CPU + tight memory + extra disk partition
+  db-01:
+    threshold_config: [tight_cpu, tight_memory, db_disk]
+
+  # Replica database: tight memory + extra disk, normal CPU
+  db-02:
+    threshold_config: [tight_memory, db_disk]
 ```
 
 ### Backward Compatibility
@@ -1012,16 +1139,25 @@ threshold_configs:
 
 ### Configuration Priority
 
-1. **Host-specific mapping**: If host is in `host_threshold_mapping`, use that config
+1. **Host `threshold_config` (list)**: Layer each named config's overrides left-to-right on top of the defaults
-2. **Default config**: Use `default_threshold_config` 
+2. **Host `threshold_config` (string)**: Use that single named config directly
-3. **First alphabetically**: If default not found, use first config alphabetically
+3. **`host_threshold_mapping`** (legacy): Same as above, string only
-4. **Legacy fallback**: If `threshold_configs` not present, use `thresholds`
+4. **`default_threshold_config`**: Used for hosts with no mapping
+5. **First alphabetically**: If the default config is not found, use the first config alphabetically
+6. **Legacy `thresholds` section**: Used when `threshold_configs` is absent entirely
 
-### Example: Complete Multi-Threshold Setup
+### Backward Compatibility
 
-See `hbd/config_multi_threshold_example.yaml` for a complete example with:
+The legacy `host_threshold_mapping` top-level key and the flat `thresholds` section are still fully supported:
-- 4 named configurations (default, high_sensitivity, low_sensitivity, database)
+
-- Host-to-config mappings for production, development, and test systems
+```yaml
-- Specialized database server thresholds
+# Still works — equivalent to hosts: {prod-web-01: {threshold_config: high_sensitivity}}
-- Custom display messages with plugin data
+host_threshold_mapping:
+  prod-web-01: high_sensitivity
+
+# Still works — equivalent to threshold_configs: {default: {thresholds: ...}}
+thresholds:
+  cpu_monitor:
+    cpu_percent: {warning: 80, critical: 90}
+```
 

hbd/Plan.md

@@ -1,21 +0,0 @@
-Plan the following changes, ask questions to clarify before implementing
-
-Re-factor the notification system:
-- use available libraries for pushover, matrix, email and sms notifications.
-- notifications have a title/subject:  alert_type (recover/warning/critical), a body (info from threshold check) and a link to the host plugin metrix page
-- define a list of notification channels for each user
-- notifications are dispatched to users that are listed as managers for the host
-
-
-
-1 - correct
-2 - for now channels are defined globaly 
-3 - matrix-nio)sounds good, homeserver URL, access token, room ID per channel?
-4 - use the REST api provided by https://voip.ms/api/v1/rest.php
-5 - The page does not exist yet, point at the host tab in the /plugins
-6 - per-channel minimum severity is a good idea, go fo it
-7 - yes
-
-1 - use base_url, there might not have been any incoming requests yet
-2 - use same asyncio loop for matrix-nio
-3 - for now, just silently do nothing

hbd/__init__.py

@@ -14,4 +14,4 @@ Install options:
 """
 
 __all__ = ["__version__"]
-__version__ = "5.1.3"
+__version__ = "5.1.16"

hbd/client/main.py

@@ -14,7 +14,6 @@ import signal
 import socket
 import sys
 import time
-from hashlib import md5
 from logging.handlers import SysLogHandler
 from pathlib import Path
 from typing import Dict, List, Optional
@@ -56,6 +55,7 @@ class AsyncConnection:
         
         self.transport: Optional[asyncio.DatagramTransport] = None
         self.protocol: Optional[asyncio.DatagramProtocol] = None
+        self._dead = False
 
         self.logger = logging.getLogger(f"hbc.conn.{addr}")
     
@@ -93,6 +93,9 @@ class AsyncConnection:
             msg: Message dictionary
             msg_id: Message ID (HTB, PLG, etc.)
         """
+        if self._dead:
+            return
+
         if not self.transport:
             await self.open()
 
@@ -167,7 +170,9 @@ class HeartbeatProtocol(asyncio.DatagramProtocol):
     
     def error_received(self, exc):
         """Handle protocol errors."""
-        self.logger.error(f"Protocol error: {exc}")
+        self.logger.warning(f"Protocol error on {self.connection.addr}: {exc} — dropping connection")
+        self.connection._dead = True
+        self.connection.close()
 
 
 async def handle_command(conn: AsyncConnection, msg: dict):
@@ -204,48 +209,45 @@ async def handle_command(conn: AsyncConnection, msg: dict):
     await conn.sendto(response)
 
 
-async def handle_update(conn: AsyncConnection, msg: dict):
+async def handle_update(conn: AsyncConnection, _msg: dict):  # pyright: ignore[reportUnusedParameter]
-    """Handle self-update from server."""
+    """Handle self-update by running hb_install.sh."""
-    import codecs
     import shutil
 
     logger = logging.getLogger("hbc.update")
 
-    try:
+    installer = shutil.which("hb_install.sh")
-        code = codecs.decode(msg["code"], "base64").decode()
+    if installer is None:
-        csum = msg["csum"]
+        candidate = Path(sys.argv[0]).parent / "hb_install.sh"
-    except Exception as e:
+        if candidate.exists():
-        error = f"Missing code/csum: {e}"
+            installer = str(candidate)
+
+    if installer is None:
+        error = "hb_install.sh not found in PATH or alongside hbc"
         logger.error(error)
         await conn.sendto({"service": "update", "msg": error})
         return
 
-    # Verify checksum
+    logger.info(f"Running installer: {installer}")
-    m = md5()
+    try:
-    m.update(code.encode())
+        proc = await asyncio.create_subprocess_exec(
-    if m.hexdigest() != csum:
+            installer, "client",
-        error = "Checksum mismatch"
+            stdout=asyncio.subprocess.PIPE,
+            stderr=asyncio.subprocess.STDOUT,
+        )
+        out, _ = await asyncio.wait_for(proc.communicate(), timeout=120)
+    except asyncio.TimeoutError:
+        error = "Installer timed out"
+        logger.error(error)
+        await conn.sendto({"service": "update", "msg": error})
+        return
+    except Exception as e:
+        error = f"Installer failed: {e}"
         logger.error(error)
         await conn.sendto({"service": "update", "msg": error})
         return
 
-    # Backup current file
+    if proc.returncode != 0:
-    fn = sys.argv[0]
+        error = f"Installer exited {proc.returncode}: {out.decode().strip()}"
-    ofn = f"{fn}.sav"
-    try:
-        shutil.copy2(fn, ofn)
-    except Exception as e:
-        error = f"Backup failed: {e}"
-        logger.error(error)
-        await conn.sendto({"service": "update", "msg": error})
-        return
-    
-    # Write new code
-    try:
-        with open(fn, "w") as fh:
-            fh.write(code)
-    except Exception as e:
-        error = f"Write failed: {e}"
         logger.error(error)
         await conn.sendto({"service": "update", "msg": error})
         return
@@ -523,6 +525,13 @@ async def async_main(args, config):
     for sig in (signal.SIGTERM, signal.SIGINT):
         loop.add_signal_handler(sig, stop)
 
+    def _sighup():
+        global dorestart
+        dorestart = True
+        stop()
+
+    loop.add_signal_handler(signal.SIGHUP, _sighup)
+    
     # Start async tasks
     # Heartbeat senders (one per connection)
     for conn in connections:

hbd/client/plugins/os_info.py

@@ -60,6 +60,7 @@ class OSInfoPlugin(InfoPlugin):
                 "python_version": platform.python_version(),
                 "python_implementation": platform.python_implementation(),
                 "hbc_version": hbc_version,
+                "hbc_type": "full",
             }
             
             # Add Linux-specific distribution info

hbd/client/plugins/zfs_monitor.py

@@ -0,0 +1,130 @@
+"""
+ZFS pool monitoring plugin for Heartbeat.
+
+Collects per-pool health, capacity, and cumulative I/O statistics via zpool(8).
+"""
+
+import asyncio
+import logging
+import shutil
+from typing import Any, Dict, List, Optional
+
+from hbd.client.plugin import MonitorPlugin
+
+logger = logging.getLogger(__name__)
+
+
+def _int(s: str) -> Optional[int]:
+    try:
+        return int(s.strip().rstrip("KMGTkBkmgt%x"))
+    except (ValueError, AttributeError):
+        return None
+
+
+def _float(s: str) -> Optional[float]:
+    try:
+        return float(s.strip().rstrip("%x"))
+    except (ValueError, AttributeError):
+        return None
+
+
+class ZFSMonitorPlugin(MonitorPlugin):
+    """Monitor ZFS pool health, capacity, and I/O statistics.
+
+    Collects per pool:
+    - health: ONLINE, DEGRADED, FAULTED, etc.
+    - size / alloc / free: total, allocated and free bytes
+    - capacity: percentage used (0-100)
+    - frag: fragmentation percentage
+    - dedup: deduplication ratio
+    - read_ops / write_ops: cumulative I/O operations since last boot/clear
+    - read_bw / write_bw: cumulative bytes transferred since last boot/clear
+
+    Configuration:
+        interval: collection interval in seconds (default: 300)
+        pools: list of pool names to monitor (default: all)
+    """
+
+    name = "zfs_monitor"
+    description = "ZFS pool health, capacity, and I/O statistics"
+    interval = 300
+
+    def __init__(self, config: Optional[Dict[str, Any]] = None):
+        super().__init__(config)
+        self.interval = self.config.get("interval", 300)
+        self._pools_filter: Optional[List[str]] = self.config.get("pools", None)
+
+    async def initialize(self) -> bool:
+        if not shutil.which("zpool"):
+            self.skip_reason = "zpool not found"
+            return False
+        logger.info("ZFS monitor initialized (interval: %ds)", self.interval)
+        return True
+
+    async def _run(self, *args: str) -> List[str]:
+        """Run a command and return its stdout lines, or [] on error."""
+        try:
+            proc = await asyncio.create_subprocess_exec(
+                *args,
+                stdout=asyncio.subprocess.PIPE,
+                stderr=asyncio.subprocess.DEVNULL,
+            )
+            stdout, _ = await asyncio.wait_for(proc.communicate(), timeout=15)
+            return stdout.decode(errors="replace").splitlines()
+        except (FileNotFoundError, asyncio.TimeoutError) as exc:
+            logger.warning("zfs_monitor: %s: %s", args[0], exc)
+            return []
+
+    async def _zpool_list(self) -> Dict[str, Dict]:
+        """Return per-pool health and capacity from `zpool list`."""
+        lines = await self._run(
+            "zpool", "list", "-H", "-p",
+            "-o", "name,health,size,alloc,free,cap,frag,dedup",
+        )
+        pools: Dict[str, Dict] = {}
+        for line in lines:
+            parts = line.split("\t")
+            if len(parts) < 8:
+                continue
+            name = parts[0].strip()
+            if self._pools_filter and name not in self._pools_filter:
+                continue
+            pools[name] = {
+                "health":   parts[1].strip(),
+                "size":     _int(parts[2]),
+                "alloc":    _int(parts[3]),
+                "free":     _int(parts[4]),
+                "capacity": _float(parts[5]),
+                "frag":     _float(parts[6]),
+                "dedup":    _float(parts[7]),
+            }
+        return pools
+
+    async def _zpool_iostat(self) -> Dict[str, Dict]:
+        """Return per-pool cumulative I/O counters from `zpool iostat`."""
+        lines = await self._run("zpool", "iostat", "-H", "-p")
+        io: Dict[str, Dict] = {}
+        for line in lines:
+            parts = line.split("\t")
+            if len(parts) < 7:
+                continue
+            name = parts[0].strip()
+            if not name or name.startswith(" "):
+                continue
+            io[name] = {
+                "read_ops": _int(parts[3]),
+                "write_ops": _int(parts[4]),
+                "read_bw":  _int(parts[5]),
+                "write_bw": _int(parts[6]),
+            }
+        return io
+
+    async def _collect_metrics(self) -> Dict[str, Any]:
+        pools, io = await asyncio.gather(self._zpool_list(), self._zpool_iostat())
+        for name, stats in io.items():
+            if name in pools:
+                pools[name].update(stats)
+        return {"pools": pools}
+
+
+plugin = ZFSMonitorPlugin

hbd/server/cli.py

@@ -144,17 +144,16 @@ def cmd_notify(args):
         url=f"{base_url}/plugins" if base_url else "",
     )
 
-    # Bypass min_level for explicit test sends; run async channels directly
     import asyncio
+    from .notify import _send_matrix_async, _send_sms_voipms_async, _DRIVERS
     ch_type = channel_cfg.get("type", "")
     print(f"Sending via {args.channel} ({ch_type}): {title} — {args.message}")
 
-    if ch_type in ("matrix", "sms_voipms"):
+    if ch_type == "matrix":
-        from .notify import _send_matrix_async, _send_sms_voipms_async
+        ok = asyncio.run(_send_matrix_async(channel_cfg, notif))
-        driver_async = _send_matrix_async if ch_type == "matrix" else _send_sms_voipms_async
+    elif ch_type == "sms_voipms":
-        ok = asyncio.run(driver_async(channel_cfg, notif))
+        ok = asyncio.run(_send_sms_voipms_async(channel_cfg, notif))
     else:
-        from .notify import _DRIVERS
         driver = _DRIVERS.get(ch_type)
         if driver is None:
             print(f"Error: unknown channel type '{ch_type}'", file=sys.stderr)

hbd/server/config.py

@@ -225,7 +225,7 @@ def get_watchhosts(config):
     hosts_config = config.get("hosts", {})
     if isinstance(hosts_config, dict):
         for host_name, host_attrs in hosts_config.items():
-            if isinstance(host_attrs, dict) and host_attrs.get("watch", False):
+            if isinstance(host_attrs, dict) and host_attrs.get("watch", True):
                 watchhosts.append(host_name)
     return watchhosts
 

hbd/server/hbdclass.py

@@ -95,7 +95,7 @@ class Connection:
         if not Null:
             d["addr"] = self.addr
             if self.rtts[-1]:
-                d["rtt"] = "%0.1f" % self.rtts[-1]
+                d["rtt"] = "%d" % round(self.rtts[-1])
             elif self.state == Connection.UNKNOWN:
                 d["rtt"] = ""
             else:
@@ -286,7 +286,7 @@ class Host:
             Host.hosts[name] = self
         self.num = num
         self.dyn = False
-        self.watched = False
+        self.watched = True
         self.upcount = 0
         self.interval = 0
         self.doesack = -1
@@ -304,6 +304,7 @@ class Host:
 
     def statedict(self):
         d = {}
+        d["raw_name"] = self.name
         d["name"] = self.name
         if self.dyn:
             d["name"] += "*"

hbd/server/http.py

@@ -1,7 +1,11 @@
 """HTTP server implementation using aiohttp and jinja2."""
 
 import asyncio
+import datetime
 import json
+import platform
+import socket
+import sys
 import time
 import urllib.parse
 import os
@@ -111,6 +115,7 @@ async def start(
     This function is intended to be awaited inside the main asyncio event loop.
     """
     get_now = get_now or (lambda: time.time())
+    _start_epoch = time.time()
 
     async def old_index(request):
         _require_auth_redirect(request)
@@ -210,15 +215,11 @@ async def start(
             return err
         qa = request.rel_url.query
         uname = urllib.parse.unquote(qa.get("h", ""))
-        ucode = qa.get("c")
+        if not uname:
-        if not ucode or not uname:
+            return web.Response(status=400, text="need h= argument")
-            return web.Response(status=400, text="need h= and c= arguments")
         if uname != "All" and uname not in hbdclass.Host.hosts:
             return web.Response(status=400, text=f"h={uname} not found")
-        if uname != "All":
+        names = [uname] if uname != "All" else list(hbdclass.Host.hosts)
-            names = [uname]
-        else:
-            names = [n for n in hbdclass.Host.hosts]
         out = []
         for n in names:
             host = hbdclass.Host.hosts[n]
@@ -227,8 +228,7 @@ async def start(
                 continue
             op_err = None
             try:
-                r = {"csum": None, "code": ucode}
+                host.cmds.append(("UPD", {}))
-                host.cmds.append(("UPD", r))
             except Exception as e:
                 op_err = str(e)
             out.append(f"update started for {n}: {op_err if op_err else 'OK'}")
@@ -258,7 +258,9 @@ async def start(
             extra_scripts=extra_scripts,
             hbd_version=hbd_version,
             hosts=[
-                hbdclass.Host.hosts[h].stateinfo() for h in sorted(hbdclass.Host.hosts)
+                hbdclass.Host.hosts[h].stateinfo()
+                for h in sorted(hbdclass.Host.hosts)
+                if _can_operate_host(current_user, hbdclass.Host.hosts[h])
             ],
             messages=data.msgs[-30:],
             current_user=current_user.to_dict() if current_user else None,
@@ -510,7 +512,7 @@ async def start(
         hosts_with_plugins = []
         for hostname in sorted(hbdclass.Host.hosts.keys()):
             host = hbdclass.Host.hosts[hostname]
-            if not _can_view_host(current_user, host):
+            if not _can_operate_host(current_user, host):
                 continue
             if host.plugin_data:
                 hosts_with_plugins.append({
@@ -520,8 +522,8 @@ async def start(
 
         tmpl = env.get_template("plugins.html")
         body = tmpl.render(
-            title="Plugin Metrics - Heartbeat",
+            title="Host Overview - Heartbeat",
-            header="Plugin Metrics",
+            header="Host Overview",
             hosts=hosts_with_plugins,
             current_user=current_user.to_dict() if current_user else None,
             active_page="plugins",
@@ -811,6 +813,48 @@ async def start(
         )
         return web.Response(text=body, content_type="text/html")
 
+    # -------------------------------------------------------------------------
+    # About page
+    # -------------------------------------------------------------------------
+
+    async def about_page(request):
+        """GET /about — version, runtime, and project information."""
+        current_user, _ = _require_auth_redirect(request)
+        pkg_dir = os.path.dirname(__file__)
+        templates_dir = config.get("templates_dir", os.path.join(pkg_dir, "templates"))
+        env = jinja2.Environment(loader=jinja2.FileSystemLoader(templates_dir))
+        from hbd import __version__ as hbd_version
+
+        uptime_secs = int(time.time() - _start_epoch)
+        days, rem = divmod(uptime_secs, 86400)
+        hours, rem = divmod(rem, 3600)
+        mins, secs = divmod(rem, 60)
+        if days:
+            uptime_str = f"{days}d {hours}h {mins}m"
+        elif hours:
+            uptime_str = f"{hours}h {mins}m {secs}s"
+        else:
+            uptime_str = f"{mins}m {secs}s"
+
+        start_dt = datetime.datetime.fromtimestamp(_start_epoch)
+        start_time_str = start_dt.strftime("%Y-%m-%d %H:%M:%S")
+
+        tmpl = env.get_template("about.html")
+        body = tmpl.render(
+            title="About - Heartbeat",
+            header="About",
+            hbd_version=hbd_version,
+            python_version=f"{sys.version_info.major}.{sys.version_info.minor}.{sys.version_info.micro} ({platform.python_implementation()})",
+            server_hostname=socket.gethostname(),
+            start_epoch=int(_start_epoch),
+            start_time_str=start_time_str,
+            uptime_str=uptime_str,
+            host_count=len(hbdclass.Host.hosts),
+            current_user=current_user.to_dict() if current_user else None,
+            active_page="about",
+        )
+        return web.Response(text=body, content_type="text/html")
+
     # -------------------------------------------------------------------------
     # Settings page (admin only)
     # -------------------------------------------------------------------------
@@ -864,6 +908,7 @@ async def start(
             web.get("/live", live),
             web.get("/plugins", plugins_page),
             web.get("/alerts", alerts_page),
+            web.get("/about", about_page),
             web.get("/profile", profile_page),
             web.get("/settings", settings_page),
             web.get("/static/{path:.*}", static),

hbd/server/main.py

@@ -210,7 +210,6 @@ async def _run_async(config, config_path=None):
         ctx = dict(
             config=config,
             hbdclass=hbdclass,
-            log=eventlog,
             msg_to_websockets=msg_to_websockets,
             msg_journal=msg_journal,
             threshold_checker=threshold_checker,
@@ -237,7 +236,6 @@ async def _run_async(config, config_path=None):
     restore_ctx = dict(
         config=config,
         hbdclass=hbdclass,
-        log=eventlog,
         msg_to_websockets=msg_to_websockets,
         threshold_checker=threshold_checker,
     )

hbd/server/notify.py

@@ -15,7 +15,6 @@ their own ``notification_channels`` list.  When no users are configured the
 server runs silently (no notifications sent).
 """
 
-import asyncio
 import asyncio
 import logging
 import smtplib
@@ -30,13 +29,10 @@ from . import ws as ws_mod
 
 logger = logging.getLogger(__name__)
 
-logger = logging.getLogger(__name__)
-
 msg_to_websockets = ws_mod.broadcast
 
 # Module-level state set via setup()
 _config: dict = {}
-_loop: Optional[asyncio.AbstractEventLoop] = None
 
 # Tracks which channels fired a WARNING/CRITICAL per host.
 # {host_name: set of channel_names}  — used to route RECOVER to the same channels.
@@ -73,11 +69,9 @@ class Notification:
 # ---------------------------------------------------------------------------
 
 def setup(cfg: dict, loop: Optional[asyncio.AbstractEventLoop] = None):
-    """Initialize notifier from configuration dict and event loop."""
+    """Initialize notifier from configuration dict."""
-    global _config, _loop
+    global _config
     _config = dict(cfg)
-    if loop is not None:
-        _loop = loop
 
 
 def reload_config(cfg: dict):
@@ -299,17 +293,6 @@ async def _send_sms_voipms_async(channel_cfg: dict, notif: Notification) -> bool
         return False
 
 
-def _send_sms_voipms(channel_cfg: dict, notif: Notification) -> bool:
-    """Dispatch voip.ms SMS send onto the shared event loop."""
-    if _loop is None:
-        logger.warning("sms_voipms: event loop not available")
-        return False
-    future = asyncio.run_coroutine_threadsafe(_send_sms_voipms_async(channel_cfg, notif), _loop)
-    try:
-        return future.result(timeout=15)
-    except Exception as e:
-        logger.error("sms_voipms send timed out or failed: %s", e)
-        return False
 
 
 async def _send_matrix_async(channel_cfg: dict, notif: Notification) -> bool:
@@ -357,40 +340,23 @@ async def _send_matrix_async(channel_cfg: dict, notif: Notification) -> bool:
         await client.close()
 
 
-def _send_matrix(channel_cfg: dict, notif: Notification) -> bool:
-    """Dispatch matrix send onto the shared event loop."""
-    if _loop is None:
-        logger.warning("matrix: event loop not available")
-        return False
-    future = asyncio.run_coroutine_threadsafe(_send_matrix_async(channel_cfg, notif), _loop)
-    try:
-        return future.result(timeout=15)
-    except Exception as e:
-        logger.error("matrix send timed out or failed: %s", e)
-        return False
-
-
 # ---------------------------------------------------------------------------
-# Channel dispatcher
+# Channel dispatcher  (all async — sync drivers run in a thread executor)
 # ---------------------------------------------------------------------------
 
+# Sync drivers kept for `hbd notify` CLI usage (asyncio.run wraps them there).
 _DRIVERS = {
     "pushover": _send_pushover,
     "email": _send_email,
     "mattermost": _send_mattermost,
     "signal": _send_signal,
-    "sms_voipms": _send_sms_voipms,
-    "matrix": _send_matrix,
 }
 
+_TIMEOUT = 15  # seconds per channel send
 
-def _dispatch_to_channel(channel_name: str, channel_cfg: dict, notif: Notification) -> bool:
-    """Send *notif* to a single named channel, honouring min_level.
 
-    RECOVER always bypasses min_level — a recovery is always relevant if the
+async def _dispatch_to_channel(channel_name: str, channel_cfg: dict, notif: Notification) -> bool:
-    channel was configured for any alerting (handles the restart-then-recover case
+    """Send *notif* to a single named channel, honouring min_level."""
-    where _alerted_channels is empty and we fall through to the normal loop).
-    """
     level = notif.level.upper()
     if level != "RECOVER":
         min_level = channel_cfg.get("min_level", "WARNING").upper()
@@ -398,14 +364,24 @@ def _dispatch_to_channel(channel_name: str, channel_cfg: dict, notif: Notificati
             logger.debug(
                 "channel '%s': skipping level %s (min_level=%s)", channel_name, level, min_level
             )
-            return True  # not an error — filtered intentionally
+            return True  # filtered intentionally
 
     ch_type = channel_cfg.get("type", "")
-    driver = _DRIVERS.get(ch_type)
+    try:
-    if driver is None:
+        if ch_type == "matrix":
-        logger.warning("unknown channel type '%s' for channel '%s'", ch_type, channel_name)
+            return await asyncio.wait_for(_send_matrix_async(channel_cfg, notif), timeout=_TIMEOUT)
+        if ch_type == "sms_voipms":
+            return await asyncio.wait_for(_send_sms_voipms_async(channel_cfg, notif), timeout=_TIMEOUT)
+        sync_driver = _DRIVERS.get(ch_type)
+        if sync_driver is None:
+            logger.warning("unknown channel type '%s' for channel '%s'", ch_type, channel_name)
+            return False
+        return await asyncio.wait_for(
+            asyncio.to_thread(sync_driver, channel_cfg, notif), timeout=_TIMEOUT
+        )
+    except asyncio.TimeoutError:
+        logger.error("channel '%s' timed out after %ds", channel_name, _TIMEOUT)
         return False
-    return driver(channel_cfg, notif)
 
 
 # ---------------------------------------------------------------------------
@@ -419,7 +395,7 @@ def _build_url(host_name: str) -> str:
     return f"{base_url}/plugins#{host_name}"
 
 
-def send_notification(host_name: str, notif: Notification) -> dict:
+async def send_notification(host_name: str, notif: Notification) -> dict:
     """Dispatch *notif* to all managers/owner of *host_name*.
 
     Looks up the host's owner + managers, resolves each user's
@@ -469,16 +445,12 @@ def send_notification(host_name: str, notif: Notification) -> dict:
             if not channel_cfg:
                 continue
             try:
-                ch_type = channel_cfg.get("type", "")
+                ok = await _dispatch_to_channel(channel_name, channel_cfg, notif)
-                driver = _DRIVERS.get(ch_type)
+                results[channel_name] = ok
-                if driver:
+                if ok:
-                    ok = driver(channel_cfg, notif)
+                    logger.info("recover sent to channel '%s': %s", channel_name, notif.title)
-                    results[channel_name] = ok
-                    if ok:
-                        logger.info("recover sent to channel '%s': %s", channel_name, notif.title)
             except Exception as e:
                 logger.error("error sending recover to channel '%s': %s", channel_name, e)
-        # Clear the alerted set once recovery is delivered
         del _alerted_channels[host_name]
         return results
 
@@ -489,14 +461,14 @@ def send_notification(host_name: str, notif: Notification) -> dict:
             continue
         for channel_name in user.notification_channels:
             if channel_name in results:
-                continue  # already dispatched to this channel this notification
+                continue
             channel_cfg = global_channels.get(channel_name)
             if not channel_cfg:
                 logger.warning("channel '%s' not defined in notification_channels", channel_name)
                 results[channel_name] = False
                 continue
             try:
-                ok = _dispatch_to_channel(channel_name, channel_cfg, notif)
+                ok = await _dispatch_to_channel(channel_name, channel_cfg, notif)
                 results[channel_name] = ok
                 if ok:
                     logger.info("notification sent to channel '%s': %s", channel_name, notif.title)

hbd/server/settings.py

@@ -24,7 +24,7 @@ sensitive   bool  True when the raw value must never be shown
 # Credential field names that should always be masked.
 _SECRET_KEYS = frozenset({
     "password", "token", "user_key", "api_key", "secret",
-    "smtp_password", "smtp_user",
+    "smtp_password", "smtp_user", "api_password", "access_token",
 })
 
 _CHANNEL_TYPE_LABELS = {
@@ -181,6 +181,48 @@ def get_settings_sections(config: dict) -> list:
             "notification_channels": attrs.get("notification_channels", []),
         })
 
+    # ---- Threshold configurations -----------------------------------------
+    def _parse_metric_row(metric_path, metric_cfg):
+        if not isinstance(metric_cfg, dict):
+            return None
+        return {
+            "metric": metric_path,
+            "operator": metric_cfg.get("operator", ">"),
+            "warning": metric_cfg.get("warning"),
+            "critical": metric_cfg.get("critical"),
+            "hysteresis": metric_cfg.get("hysteresis"),
+            "count": metric_cfg.get("count", 1),
+            "enabled": metric_cfg.get("enabled", True),
+        }
+
+    threshold_config_list = []
+    raw_tconfigs = config.get("threshold_configs") or {}
+    if raw_tconfigs:
+        for cfg_name, cfg_data in sorted(raw_tconfigs.items()):
+            if not isinstance(cfg_data, dict):
+                continue
+            metrics = [
+                r for r in (
+                    _parse_metric_row(mp, mc)
+                    for mp, mc in (cfg_data.get("thresholds") or {}).items()
+                ) if r
+            ]
+            threshold_config_list.append({
+                "name": cfg_name,
+                "metrics": sorted(metrics, key=lambda m: m["metric"]),
+            })
+    elif config.get("thresholds"):
+        metrics = [
+            r for r in (
+                _parse_metric_row(mp, mc)
+                for mp, mc in config["thresholds"].items()
+            ) if r
+        ]
+        threshold_config_list.append({
+            "name": "default",
+            "metrics": sorted(metrics, key=lambda m: m["metric"]),
+        })
+
     # ---- Hosts summary ----------------------------------------------------
     hosts_list = []
     for hname, hcfg in (config.get("hosts") or {}).items():
@@ -188,7 +230,7 @@ def get_settings_sections(config: dict) -> list:
             continue
         hosts_list.append({
             "name": hname,
-            "watch": bool(hcfg.get("watch", False)),
+            "watch": bool(hcfg.get("watch", True)),
             "dyndns": bool(hcfg.get("dyndns", False)),
             "owner": hcfg.get("owner", ""),
             "managers": hcfg.get("managers", []),
@@ -312,6 +354,16 @@ def get_settings_sections(config: dict) -> list:
             "hosts": hosts_list,
             "fields": [],
         },
+        {
+            "id": "thresholds",
+            "title": "Threshold Configurations",
+            "description": "Named alert threshold sets. Each defines warning/critical levels per metric.",
+            "threshold_configs": threshold_config_list,
+            "fields": [
+                field("default_threshold_config", "Default config", "text",
+                      "Threshold config used for hosts with no explicit mapping."),
+            ],
+        },
         {
             "id": "runtime",
             "title": "Runtime",

hbd/server/templates/about.html

@@ -0,0 +1,199 @@
+<!DOCTYPE html>
+<html>
+  {% include 'head.html' %}
+
+  <style>
+    html, body { overflow: visible; }
+
+    .container {
+      max-width: 700px;
+      margin: 0 auto;
+    }
+
+    h1 {
+      color: #333;
+      margin-bottom: 4px;
+      font-size: 1.5em;
+    }
+
+    .subtitle {
+      color: #666;
+      margin-bottom: 24px;
+      font-size: 0.9em;
+    }
+
+    .section {
+      background: #fff;
+      border-radius: 8px;
+      box-shadow: 0 1px 6px rgba(0,0,0,0.1);
+      padding: 20px 24px;
+      margin-bottom: 20px;
+    }
+
+    .section h2 {
+      font-size: 1em;
+      font-weight: 700;
+      color: #333;
+      margin: 0 0 16px;
+      padding-bottom: 10px;
+      border-bottom: 1px solid #eee;
+      text-transform: uppercase;
+      letter-spacing: 0.5px;
+    }
+
+    .info-row {
+      display: flex;
+      align-items: baseline;
+      padding: 8px 0;
+      border-bottom: 1px solid #f5f5f5;
+      font-size: 0.9em;
+    }
+    .info-row:last-child { border-bottom: none; }
+
+    .info-label {
+      width: 160px;
+      flex-shrink: 0;
+      color: #666;
+      font-size: 0.88em;
+    }
+
+    .info-value {
+      color: #222;
+      word-break: break-all;
+    }
+
+    .info-value a {
+      color: #0066cc;
+      text-decoration: none;
+    }
+    .info-value a:hover { text-decoration: underline; }
+
+    .version-badge {
+      display: inline-block;
+      padding: 3px 12px;
+      background: #e8f0fe;
+      color: #1a73e8;
+      border-radius: 12px;
+      font-size: 0.85em;
+      font-weight: 600;
+      font-family: monospace;
+    }
+
+    .hb-logo {
+      font-size: 2.5em;
+      font-weight: 700;
+      color: #0066cc;
+      letter-spacing: -1px;
+      margin-bottom: 6px;
+    }
+
+    .hb-tagline {
+      color: #555;
+      font-size: 0.95em;
+    }
+
+    .logo-section {
+      display: flex;
+      align-items: center;
+      gap: 20px;
+      padding: 8px 0 4px;
+    }
+
+    .logo-text { flex: 1; }
+  </style>
+
+  <body>
+    {% include 'nav.html' %}
+
+    <div class="container">
+      <h1>{{ header }}</h1>
+      <p class="subtitle">Heartbeat monitoring system</p>
+
+      <div class="section">
+        <div class="logo-section">
+          <div class="logo-text">
+            <div class="hb-logo">Heartbeat</div>
+            <div class="hb-tagline">Lightweight host monitoring over UDP</div>
+          </div>
+          <span class="version-badge">v{{ hbd_version }}</span>
+        </div>
+      </div>
+
+      <div class="section">
+        <h2>Version</h2>
+        <div class="info-row">
+          <span class="info-label">Server version</span>
+          <span class="info-value">{{ hbd_version }}</span>
+        </div>
+        <div class="info-row">
+          <span class="info-label">Python</span>
+          <span class="info-value">{{ python_version }}</span>
+        </div>
+        <div class="info-row">
+          <span class="info-label">License</span>
+          <span class="info-value">MIT</span>
+        </div>
+      </div>
+
+      <div class="section">
+        <h2>Runtime</h2>
+        <div class="info-row">
+          <span class="info-label">Host</span>
+          <span class="info-value">{{ server_hostname }}</span>
+        </div>
+        <div class="info-row">
+          <span class="info-label">Started</span>
+          <span class="info-value">{{ start_time_str }}</span>
+        </div>
+        <div class="info-row">
+          <span class="info-label">Uptime</span>
+          <span class="info-value" id="uptime-value">{{ uptime_str }}</span>
+        </div>
+        <div class="info-row">
+          <span class="info-label">Hosts monitored</span>
+          <span class="info-value">{{ host_count }}</span>
+        </div>
+      </div>
+
+      <div class="section">
+        <h2>Contact &amp; Source</h2>
+        <div class="info-row">
+          <span class="info-label">Author</span>
+          <span class="info-value">Andreas Wrede</span>
+        </div>
+        <div class="info-row">
+          <span class="info-label">Email</span>
+          <span class="info-value"><a href="mailto:aew@wrede.ca">aew@wrede.ca</a></span>
+        </div>
+        <div class="info-row">
+          <span class="info-label">Repository</span>
+          <span class="info-value"><a href="https://git.wrede.ca/andreas/heartbeat" target="_blank" rel="noopener">git.wrede.ca/andreas/heartbeat</a></span>
+        </div>
+      </div>
+
+    </div>
+
+    <script>
+      (function() {
+        var startEpoch = {{ start_epoch }};
+        var el = document.getElementById('uptime-value');
+        if (!el) return;
+        function fmt(s) {
+          var d = Math.floor(s / 86400);
+          var h = Math.floor((s % 86400) / 3600);
+          var m = Math.floor((s % 3600) / 60);
+          var sec = s % 60;
+          if (d > 0) return d + 'd ' + h + 'h ' + m + 'm';
+          if (h > 0) return h + 'h ' + m + 'm ' + sec + 's';
+          return m + 'm ' + sec + 's';
+        }
+        function tick() {
+          var up = Math.floor(Date.now() / 1000 - startEpoch);
+          el.textContent = fmt(up);
+        }
+        tick();
+        setInterval(tick, 1000);
+      })();
+    </script>
+  </body>
+</html>

hbd/server/templates/alerts.html

@@ -9,7 +9,7 @@
       margin: 0 auto;
     }
 
-    h1 { color: #333; margin-bottom: 10px; font-size: 1.5em; }
+    h1 { color: #333; margin-bottom: 5px; margin-top: 15px; font-size: 1.5em; }
 
     .subtitle {
       color: #666;

hbd/server/templates/head.html

@@ -15,6 +15,7 @@
       body {
         margin: 0;
         padding: 10px;
+        padding-top: 60px;
         background: #f5f5f5;
       }
       h1 { font-size: 1.5em; color: #333; margin: 0 0 5px; }
@@ -23,11 +24,14 @@
 
       /* Navigation bar — shared across all pages */
       .nav {
+        position: fixed;
+        top: 0;
+        left: 0;
+        right: 0;
+        z-index: 200;
         background: #fff;
         padding: 6px 12px;
-        margin-bottom: 10px;
         box-shadow: 0 2px 4px rgba(0,0,0,.1);
-        border-radius: 4px;
         display: flex;
         align-items: center;
         justify-content: space-between;

hbd/server/templates/live.html

@@ -45,6 +45,7 @@
     h1 {
       color: #333;
       margin-bottom: 5px;
+      margin-top: 15px; 
       font-size: 1.5em;
     }
 
@@ -235,6 +236,8 @@
       color: #ff9800;
       font-weight: 700;
     }
+    #ntable a.host-link { color: inherit; text-decoration: none; }
+    #ntable a.host-link:hover { text-decoration: underline; }
   </style>
   <script type="text/javascript">
     var cnt = 0;
@@ -244,11 +247,13 @@
     var HBD_VERSION = "{{ hbd_version }}";
 
     function hostNameHtml(data) {
+      var rawName = data.raw_name || data.name.replace(/<[^>]+>/g, '').replace('*', '').trim();
       var nameHtml = data.name;
       if (!data.hbc_version || data.hbc_version !== HBD_VERSION) {
         nameHtml += ' 🥀';
       }
-      return data.dyn ? '<b>' + nameHtml + '</b>' : nameHtml;
+      var display = data.dyn ? '<b>' + nameHtml + '</b>' : nameHtml;
+      return '<a class="host-link" href="/plugins#' + encodeURIComponent(rawName) + '">' + display + '</a>';
     }
 
     function setup() {
@@ -403,7 +408,7 @@
         );
         if (data.connections[i].state == "up") {
           state = '<span class="state-up">up</span>';
-          latency = Number.parseFloat(data.connections[i].rtts[0]).toFixed(2);
+          latency = String(Math.round(Number.parseFloat(data.connections[i].rtts[0])));
         } else {
           if (data.connections[i].state == "unknown") {
             state = "";
@@ -510,7 +515,7 @@
           <tbody id="ntablebody">
             {% for host in hosts %}
             <tr class="{% if host.alert_critical_unacked > 0 or host.alert_critical_acked > 0 %}row-critical{% elif host.alert_warning_unacked > 0 or host.alert_warning_acked > 0 %}row-warning{% endif %}">
-              <td data-name="{{ host.name }}">{{ host.name }}{% if not host.hbc_version or host.hbc_version != hbd_version %} 🥀{% endif %}</td>
+              <td data-name="{{ host.name }}"><a class="host-link" href="/plugins#{{ host.raw_name | urlencode }}">{{ host.name }}{% if not host.hbc_version or host.hbc_version != hbd_version %} 🥀{% endif %}</a></td>
               <td style="text-align: center; color: #ff9800; font-weight: bold;">
                 {%- set warning_unacked = host.alert_warning_unacked -%}
                 {%- set warning_acked = host.alert_warning_acked -%}

hbd/server/templates/nav.html

@@ -4,11 +4,12 @@
   </button>
   <div class="nav-links" id="nav-links">
     <a href="/live"{% if active_page == "live" %} class="active"{% endif %}>Live Dashboard</a>
-    <a href="/plugins"{% if active_page == "plugins" %} class="active"{% endif %}>Plugin Metrics</a>
+    <a href="/plugins"{% if active_page == "plugins" %} class="active"{% endif %}>Host Overview</a>
     <a href="/alerts"{% if active_page == "alerts" %} class="active"{% endif %}>Alerts</a>
     {% if current_user and current_user.admin %}
     <a href="/settings"{% if active_page == "settings" %} class="active"{% endif %}>Settings</a>
     {% endif %}
+    <a href="/about"{% if active_page == "about" %} class="active"{% endif %}>About</a>
   </div>
   <div class="nav-clock" title="Click for full-screen clock">
     <canvas id="swiss-clock" width="44" height="44"></canvas>

hbd/server/templates/settings.html

@@ -9,7 +9,7 @@
       max-width: 960px;
     }
 
-    h1 { color: #333; margin-bottom: 4px; font-size: 1.5em; }
+    h1 { color: #333; margin-bottom: 5px; margin-top: 15px; font-size: 1.5em; }
     .subtitle { color: #666; margin-bottom: 24px; font-size: 0.9em; }
 
     /* ---- Sidebar + content layout ---- */
@@ -23,7 +23,7 @@
       width: 180px;
       flex-shrink: 0;
       position: sticky;
-      top: 20px;
+      top: 60px;
     }
 
     .sidebar-nav a {
@@ -254,6 +254,17 @@
     .host-bool { text-align: center; }
     .dot-yes { color: #2e7d32; font-size: 1.1em; }
     .dot-no  { color: #ddd;    font-size: 1.1em; }
+
+    /* ---- Threshold configurations ---- */
+    .thresh-config { margin: 12px 20px 20px; }
+    .thresh-config-name {
+      font-weight: 600; font-size: 0.9em; color: #1a237e;
+      margin-bottom: 6px;
+    }
+    .mini-table .warn  { color: #e65100; font-weight: 600; }
+    .mini-table .crit  { color: #b71c1c; font-weight: 600; }
+    .mini-table .dim   { color: #aaa; }
+    .mini-table .metric-path { font-family: monospace; font-size: 0.88em; }
   </style>
 
   <body>
@@ -394,6 +405,49 @@
             {% endif %}
             {% endif %}
 
+            {# ---- Threshold configurations section ---- #}
+            {% if section.id == "thresholds" %}
+            {% if section.threshold_configs %}
+            {% for tc in section.threshold_configs %}
+            <div class="thresh-config">
+              <div class="thresh-config-name">{{ tc.name }}</div>
+              {% if tc.metrics %}
+              <div style="overflow-x: auto;">
+                <table class="mini-table">
+                  <thead>
+                    <tr>
+                      <th>Metric</th>
+                      <th>Op</th>
+                      <th>Warning</th>
+                      <th>Critical</th>
+                      <th>Hysteresis</th>
+                      <th>Count</th>
+                    </tr>
+                  </thead>
+                  <tbody>
+                    {% for m in tc.metrics %}
+                    <tr {% if not m.enabled %} style="opacity:0.45"{% endif %}>
+                      <td class="metric-path">{{ m.metric }}</td>
+                      <td>{{ m.operator or '>' }}</td>
+                      <td class="warn">{{ m.warning if m.warning is not none else '—' }}</td>
+                      <td class="crit">{{ m.critical if m.critical is not none else '—' }}</td>
+                      <td class="dim">{{ '%.0f%%' % (m.hysteresis * 100) if m.hysteresis else '—' }}</td>
+                      <td class="dim">{{ m.count }}</td>
+                    </tr>
+                    {% endfor %}
+                  </tbody>
+                </table>
+              </div>
+              {% else %}
+              <span class="val-empty">No thresholds defined.</span>
+              {% endif %}
+            </div>
+            {% endfor %}
+            {% else %}
+            <div class="field-row"><span class="val-empty">No threshold configurations defined.</span></div>
+            {% endif %}
+            {% endif %}
+
             {# ---- Hosts section ---- #}
             {% if section.id == "hosts" %}
             {% if section.hosts %}

hbd/server/threshold.py

@@ -9,10 +9,11 @@ This module provides a flexible threshold checking system that:
 - Supports multiple comparison operators
 """
 
+import asyncio
 import logging
 import time
 from enum import Enum
-from typing import Dict, Any, Optional, Tuple, Callable
+from typing import Dict, List, Any, Optional, Tuple, Callable
 from . import notify as notify_mod
 from .config import THRESHOLD_DEFAULTS
 
@@ -328,14 +329,17 @@ class ThresholdChecker:
             renotify_interval: Seconds between repeat notifications (default: 1 hour)
             journal: Optional MessageJournal instance for logging threshold events
         """
-        # Named threshold configurations: {config_name: {metric_path: ThresholdConfig}}
+        # Named threshold configurations (pre-merged: defaults + overrides): {config_name: {metric_path: ThresholdConfig}}
         self.threshold_configs = {}
 
+        # Raw overrides only for each named config (no defaults baked in): {config_name: {metric_path: ThresholdConfig}}
+        self.threshold_raw_configs: Dict[str, Dict[str, ThresholdConfig]] = {}
+
         # Single threshold set for backward compatibility: {metric_path: ThresholdConfig}
         self.thresholds = {}
 
-        # Host to config name mapping: {host_name: config_name}
+        # Host to ordered list of config names: {host_name: [config_name, ...]}
-        self.host_config_mapping = {}
+        self.host_config_mapping: Dict[str, List[str]] = {}
 
         # Default config name to use when no mapping exists
         self.default_config = "default"
@@ -372,6 +376,7 @@ class ThresholdChecker:
         
         # Clear old configuration
         self.threshold_configs.clear()
+        self.threshold_raw_configs.clear()
         self.thresholds.clear()
         self.host_config_mapping.clear()
         self.grace_seconds = float(config.get("grace", 2))
@@ -424,9 +429,10 @@ class ThresholdChecker:
                         self._parse_plugin_thresholds(plugin_name, plugin_thresholds, target_dict=effective_defaults)
 
         self.threshold_configs["default"] = dict(effective_defaults)
+        self.threshold_raw_configs["default"] = {}
         logger.info("Registered 'default' threshold config with %d metrics", len(effective_defaults))
 
-        # Parse each named configuration, seeding it with effective_defaults first
+        # Parse each named configuration
         for config_name, config_data in threshold_configs.items():
             if config_name == "default":
                 continue  # already handled above
@@ -440,33 +446,41 @@ class ThresholdChecker:
                 continue
 
             logger.info("Parsing threshold configuration: %s", config_name)
-            self.threshold_configs[config_name] = dict(effective_defaults)
 
+            # Raw overrides only (used for multi-config layering)
+            raw_overrides: Dict[str, ThresholdConfig] = {}
             thresholds_config = config_data["thresholds"]
             for plugin_name, plugin_thresholds in thresholds_config.items():
-                if not isinstance(plugin_thresholds, dict):
+                if isinstance(plugin_thresholds, dict):
-                    continue
+                    self._parse_plugin_thresholds(plugin_name, plugin_thresholds, target_dict=raw_overrides)
+            self.threshold_raw_configs[config_name] = raw_overrides
 
-                self._parse_plugin_thresholds(
+            # Pre-merged version (defaults + overrides) for single-config fast path
-                    plugin_name,
+            self.threshold_configs[config_name] = dict(effective_defaults)
-                    plugin_thresholds,
+            self.threshold_configs[config_name].update(raw_overrides)
-                    target_dict=self.threshold_configs[config_name]
-                )
 
-        # Parse host to config mapping from two possible sources
+        # Parse host → config list mapping from two possible sources
-        # 1. New format: hosts section with threshold_config attribute
+
+        def _normalise(value) -> List[str]:
+            """Accept a string or list; always return a list."""
+            if isinstance(value, list):
+                return [str(v) for v in value]
+            return [str(value)]
+
+        # 1. hosts section with threshold_config attribute (string or list)
         if "hosts" in config:
             hosts_config = config["hosts"]
             if isinstance(hosts_config, dict):
                 for host_name, host_attrs in hosts_config.items():
                     if isinstance(host_attrs, dict) and "threshold_config" in host_attrs:
-                        self.host_config_mapping[host_name] = host_attrs["threshold_config"]
+                        self.host_config_mapping[host_name] = _normalise(host_attrs["threshold_config"])
 
-        # 2. Legacy format: host_threshold_mapping section (for backward compatibility)
+        # 2. Legacy host_threshold_mapping section (string values only)
         if "host_threshold_mapping" in config:
             legacy_mapping = config.get("host_threshold_mapping", {})
             if isinstance(legacy_mapping, dict):
-                self.host_config_mapping.update(legacy_mapping)
+                for host_name, value in legacy_mapping.items():
+                    self.host_config_mapping[host_name] = _normalise(value)
         
         # Set default config (first one alphabetically or explicitly set)
         self.default_config = config.get("default_threshold_config", "default")
@@ -664,7 +678,10 @@ class ThresholdChecker:
         )
     
     def get_thresholds_for_host(self, host_name: str) -> Dict[str, ThresholdConfig]:
-        """Get the appropriate threshold configuration for a host.
+        """Get the effective threshold configuration for a host.
+
+        When threshold_config is a list, configs are applied left-to-right on top
+        of the default thresholds so earlier entries can be overridden by later ones.
 
         Args:
             host_name: Name of the host
@@ -676,23 +693,40 @@ class ThresholdChecker:
         if self.thresholds and not self.threshold_configs:
             return self.thresholds
 
-        # Multi-config mode: look up host-specific configuration
+        if not self.threshold_configs:
-        if self.threshold_configs:
+            return {}
-            config_name = self.host_config_mapping.get(host_name, self.default_config)
 
-            if config_name in self.threshold_configs:
+        config_names = self.host_config_mapping.get(host_name)
-                return self.threshold_configs[config_name]
+
-            else:
+        # No host-specific mapping → return pre-merged default
+        if not config_names:
+            return self.threshold_configs.get(self.default_config, {})
+
+        # Single config → fast path using pre-merged copy
+        if len(config_names) == 1:
+            name = config_names[0]
+            if name in self.threshold_configs:
+                return self.threshold_configs[name]
+            logger.warning(
+                "Threshold config '%s' not found for host '%s', using default '%s'",
+                name, host_name, self.default_config,
+            )
+            return self.threshold_configs.get(self.default_config, {})
+
+        # Multiple configs → start from defaults, layer raw overrides in order
+        result = dict(self.threshold_configs.get(self.default_config, {}))
+        for name in config_names:
+            if name == self.default_config:
+                continue  # defaults already the base
+            raw = self.threshold_raw_configs.get(name)
+            if raw is None:
                 logger.warning(
-                    "Threshold config '%s' not found for host '%s', using default '%s'",
+                    "Threshold config '%s' not found for host '%s', skipping",
-                    config_name,
+                    name, host_name,
-                    host_name,
-                    self.default_config
                 )
-                return self.threshold_configs.get(self.default_config, {})
+            else:
-        
+                result.update(raw)
-        # No thresholds configured
+        return result
-        return {}
     
     def check_value(
         self,
@@ -769,6 +803,29 @@ class ThresholdChecker:
             self._check_pending_or_renotify(host_name, alert_state, metric_path, value, threshold, None)
 
         return None
+    def _find_threshold(
+        self, thresholds: Dict[str, "ThresholdConfig"], metric_path: str
+    ) -> Optional["ThresholdConfig"]:
+        """Return the threshold for *metric_path*, falling back to suffix matches.
+
+        Allows generic thresholds like ``ping_monitor.rtt_avg`` to match
+        fully-qualified paths like ``ping_monitor.8_8_8_8_rtt_avg``.
+        The exact match is always tried first; then successive leading
+        underscore-delimited segments are stripped from the field name until
+        a match is found or no segments remain.
+        """
+        if metric_path in thresholds:
+            return thresholds[metric_path]
+        plugin, sep, field = metric_path.partition(".")
+        if not sep:
+            return None
+        parts = field.split("_")
+        for i in range(1, len(parts)):
+            candidate = plugin + "." + "_".join(parts[i:])
+            if candidate in thresholds:
+                return thresholds[candidate]
+        return None
+
     def check_plugin_data(
         self,
         host_name: str,
@@ -797,11 +854,10 @@ class ThresholdChecker:
         for metric_name, value in data.items():
             metric_path = f"{plugin_name}.{metric_name}"
             
-            if metric_path not in thresholds:
+            threshold = self._find_threshold(thresholds, metric_path)
+            if threshold is None:
                 continue
             
-            threshold = thresholds[metric_path]
-            
             # Get or create alert state
             if metric_path not in alert_states:
                 alert_states[metric_path] = AlertState(metric_path)
@@ -987,23 +1043,23 @@ class ThresholdChecker:
         value: Any,
     ):
         """Send notification and log to journal/eventlog."""
-        try:
+        from . import hbdclass
-            notify_mod.send_notification(
+        host = hbdclass.Host.hosts.get(host_name)
-                host_name,
+        if host is not None and not host.watched:
-                notify_mod.Notification(
+            eventlog(host_name, lvl, message, service="threshold")
-                    title=f"[{lvl}] {host_name}",
+            return
-                    body=message,
+        asyncio.get_event_loop().create_task(notify_mod.send_notification(
-                    level=lvl,
+            host_name,
-                ),
+            notify_mod.Notification(
-            )
+                title=f"[{lvl}] {host_name}",
-            logger.info("Notification sent: %s", message)
+                body=message,
-        except Exception as e:
+                level=lvl,
-            logger.error("Failed to send notification: %s", e)
+            ),
+        ))
         
         # Log to journal
         if self.journal is not None:
             try:
-                import asyncio
                 loop = asyncio.get_event_loop()
                 loop.create_task(self.journal.log_threshold_event(
                     host_name=host_name,
@@ -1080,7 +1136,9 @@ class ThresholdChecker:
     ) -> None:
         """Handle a state-change transition with grace-period logic.
 
-        Transitioning INTO alert: defers the notification for grace_seconds.
+        Transitioning INTO alert (worsening): defers the notification for grace_seconds.
+        De-escalation within alert states (e.g. CRITICAL→WARNING): no new notification;
+          the metric is still alerting so no RECOVER was sent.
         Transitioning TO OK:
           - Still in grace window (pending_since set): suppresses both the alert
             and the recovery — the spike never warranted a page.
@@ -1100,12 +1158,20 @@ class ThresholdChecker:
                 alert_state.pending_since = None
             else:
                 self._send_notification(host_name, lvl, message, metric_path, old_level, new_level, value)
-        else:
+        elif new_level.value > old_level.value:
+            # Worsening (OK→WARNING, OK→CRITICAL, WARNING→CRITICAL): schedule notification.
             alert_state.pending_since = time.time()
             logger.debug(
                 "Alert deferred (%.0fs grace): %s on %s = %s",
                 self.grace_seconds, metric_path, host_name, value,
             )
+        else:
+            # De-escalation within alert states (e.g. CRITICAL→WARNING): metric is still
+            # alerting but did not recover, so no new notification.
+            logger.debug(
+                "De-escalation %s→%s for %s on %s, no notification",
+                old_level.name, new_level.name, metric_path, host_name,
+            )
 
     def _check_pending_or_renotify(
         self,
@@ -1195,20 +1261,20 @@ class ThresholdChecker:
             else:
                 message = f"REMINDER ({alert_state.level.name}): {host_name} - {metric_path} = {value} (ongoing for {int(now - alert_state.since)}s)"
             
-            try:
+            from . import hbdclass
-                notify_mod.send_notification(
+            host = hbdclass.Host.hosts.get(host_name)
+            if host is None or host.watched:
+                asyncio.get_event_loop().create_task(notify_mod.send_notification(
                     host_name,
                     notify_mod.Notification(
                         title=f"[REMINDER/{alert_state.level.name}] {host_name}",
                         body=message,
                         level=alert_state.level.name,
                     ),
-                )
+                ))
-                alert_state.last_notification = now
-                alert_state.notification_count += 1
                 logger.info("Re-notification sent: %s", message)
-            except Exception as e:
+            alert_state.last_notification = now
-                logger.error("Failed to send re-notification: %s", e)
+            alert_state.notification_count += 1
     
     def get_active_alerts(self, alert_states: Dict[str, AlertState]) -> list:
         """

hbd/server/udp.py

@@ -211,10 +211,11 @@ def _make_timer_callbacks(uname, host, ctx):
         connection.newstate(connection.__class__.OVERDUE, now, cfg.get("grace", 2))
         msg = f"{connection.afam} overdue"
         eventlog(uname, "CRITICAL", msg)
-        notify_mod.send_notification(
+        if host.watched:
-            uname,
+            asyncio.create_task(notify_mod.send_notification(
-            notify_mod.Notification(title=f"[CRITICAL] {uname}", body=msg, level="CRITICAL"),
+                uname,
-        )
+                notify_mod.Notification(title=f"[CRITICAL] {uname}", body=msg, level="CRITICAL"),
+            ))
         # Track in alert_states so the Alerts Dashboard shows this
         _set_connectivity_alert(host, connection.afam, "CRITICAL")
         if threshold_checker:
@@ -315,7 +316,6 @@ def handle_datagram(msg: dict, addr, transport, ctx: dict):
     
     cfg = ctx.get("config", {})
     hbdcls = ctx.get("hbdclass")
-    log = ctx.get("log")
     msg_to_websockets = ctx.get("msg_to_websockets")
     DEBUG = ctx.get("DEBUG", 0)
     verbose = ctx.get("verbose", False)
@@ -408,10 +408,11 @@ def handle_datagram(msg: dict, addr, transport, ctx: dict):
 
     if res:
         eventlog(uname, "WARNING", res)
-        notify_mod.send_notification(
+        if host.watched:
-            uname,
+            asyncio.create_task(notify_mod.send_notification(
-            notify_mod.Notification(title=f"[WARNING] {uname}", body=res, level="WARNING"),
+                uname,
-        )
+                notify_mod.Notification(title=f"[WARNING] {uname}", body=res, level="WARNING"),
+            ))
 
     interval = int(msg.get("interval", 0) or 0)
     shutdown = msg.get("shutdown", 0)
@@ -421,10 +422,11 @@ def handle_datagram(msg: dict, addr, transport, ctx: dict):
 
     if boot:
         eventlog(uname, "INFO", "booted")
-        notify_mod.send_notification(
+        if host.watched:
-            uname,
+            asyncio.create_task(notify_mod.send_notification(
-            notify_mod.Notification(title=f"[INFO] {uname}", body=f"{host.name} booted", level="INFO"),
+                uname,
-        )
+                notify_mod.Notification(title=f"[INFO] {uname}", body=f"{host.name} booted", level="INFO"),
+            ))
     if message:
         eventlog(uname, "INFO", "msg: %s" % message, service=service)
 
@@ -438,13 +440,18 @@ def handle_datagram(msg: dict, addr, transport, ctx: dict):
         if not newh:
             if d == 0 or lasts == "unknown":
                 m = "%s is up" % (conn.afam)
+            elif d < 4:
+                # Transient blip (likely client restart) — skip log and notification
+                m = None
             else:
                 m = "%s back after being %s for %s" % (conn.afam, lasts, dur(d))
-            eventlog(uname, "RECOVER", m)
+            if m:
-            notify_mod.send_notification(
+                eventlog(uname, "RECOVER", m)
-                uname,
+                if host.watched:
-                notify_mod.Notification(title=f"[RECOVER] {uname}", body=m, level="RECOVER"),
+                    asyncio.create_task(notify_mod.send_notification(
-            )
+                        uname,
+                        notify_mod.Notification(title=f"[RECOVER] {uname}", body=m, level="RECOVER"),
+                    ))
 
     if boot or newh:
         host.upcount = host.doesack
@@ -454,10 +461,11 @@ def handle_datagram(msg: dict, addr, transport, ctx: dict):
     if shutdown:
         m = "%s shutdown" % conn.afam
         eventlog(uname, "INFO", m)
-        notify_mod.send_notification(
+        if host.watched:
-            uname,
+            asyncio.create_task(notify_mod.send_notification(
-            notify_mod.Notification(title=f"[INFO] {uname}", body=m, level="INFO"),
+                uname,
-        )
+                notify_mod.Notification(title=f"[INFO] {uname}", body=m, level="INFO"),
+            ))
         conn.newstate(hbdcls.Connection.DOWN, now)
         _set_connectivity_alert(host, conn.afam, "CRITICAL")
 
@@ -491,12 +499,10 @@ def handle_datagram(msg: dict, addr, transport, ctx: dict):
         op, rmsg = host.cmds[0]
         if op == "CMD":
             del host.cmds[0]
-            if log:
+            eventlog(uname, "INFO", "command sent")
-                log(uname, "command sent")
         elif op == "UPD":
             del host.cmds[0]
-            if log:
+            eventlog(uname, "INFO", "update initiated")
-                log(uname, "update initiated")
         opkt = dicttos(op, rmsg)
         try:
             transport.sendto(opkt, addr)

hbd/server/ws.py

@@ -13,7 +13,8 @@ from . import data
 
 logger = logging.getLogger(__name__)
 
-_connections: set = set()
+# Map of WebSocket → User object (or None when auth is disabled)
+_connections: dict = {}
 _loop: Optional[asyncio.AbstractEventLoop] = None
 _get_hosts: Optional[Callable[[], Iterable]] = None
 _verbose: bool = False
@@ -34,23 +35,53 @@ def setup(
     _verbose = verbose
 
 
+def _user_can_see_host(user, host_name: str) -> bool:
+    """Return True if *user* may see updates for *host_name* (manager or higher)."""
+    from . import hbdclass, users as users_mod
+    if user is None or not users_mod.users_enabled():
+        return True
+    if user.admin:
+        return True
+    host = hbdclass.Host.hosts.get(host_name)
+    if host is None:
+        return False
+    return host.is_manager(user.username)
+
+
+def _get_token(request) -> str:
+    """Extract session token from request (mirrors logic in http.py)."""
+    auth = request.headers.get("Authorization", "")
+    if auth.startswith("Bearer "):
+        return auth[7:].strip()
+    token = request.headers.get("X-Auth-Token", "")
+    if token:
+        return token
+    return request.cookies.get("hbd_session", "")
+
+
 async def handler(request):
     """aiohttp WebSocket upgrade handler — register as GET /ws."""
     from aiohttp import web
+    from . import users as users_mod
 
     ws = web.WebSocketResponse()
     await ws.prepare(request)
 
-    _connections.add(ws)
+    token = _get_token(request)
+    user = users_mod.get_session_user(token) if token else None
+
+    _connections[ws] = user
     remote = request.remote
     logger.info("WebSocket connected from %s", remote)
 
     try:
-        # Send current host state to the new client
+        # Send current host state, filtered to hosts this user may see
         if _get_hosts:
             try:
                 for h in list(_get_hosts()):
-                    await ws.send_str(json.dumps({"type": "host", "data": h}))
+                    host_name = h.get("raw_name") or h.get("name", "")
+                    if _user_can_see_host(user, host_name):
+                        await ws.send_str(json.dumps({"type": "host", "data": h}))
             except Exception as e:
                 logger.error("Error sending initial hosts: %s", e)
 
@@ -74,7 +105,7 @@ async def handler(request):
     except Exception as e:
         logger.exception("WebSocket handler error from %s: %s", remote, e)
     finally:
-        _connections.discard(ws)
+        _connections.pop(ws, None)
         logger.info("WebSocket disconnected from %s", remote)
 
     return ws
@@ -83,25 +114,37 @@ async def handler(request):
 def broadcast(typ: str, payload) -> bool:
     """Thread-safe broadcast to all connected WebSocket clients.
 
+    For host and plugin updates, only sends to clients whose user has
+    manager-or-higher access to that host.  Other message types are
+    broadcast to all clients.
+
     Can be called from any thread; schedules sends on the event loop.
     Returns False if the loop is not running yet.
     """
     if not _loop:
         return False
+
+    # Determine the host name for access-filtered message types
+    host_name: Optional[str] = None
+    if typ in ("host", "plugin"):
+        host_name = payload.get("raw_name") or payload.get("host") or payload.get("name")
+
     jmsg = json.dumps({"type": typ, "data": payload})
 
     async def _send_all():
         dead = set()
-        for ws in list(_connections):
+        for ws, user in list(_connections.items()):
             try:
-                if not ws.closed:
+                if ws.closed:
-                    await ws.send_str(jmsg)
-                else:
                     dead.add(ws)
+                    continue
+                if host_name is not None and not _user_can_see_host(user, host_name):
+                    continue
+                await ws.send_str(jmsg)
             except Exception:
                 dead.add(ws)
         for ws in dead:
-            _connections.discard(ws)
+            _connections.pop(ws, None)
 
     asyncio.run_coroutine_threadsafe(_send_all(), _loop)
     return True

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "hbd"
-version = "5.1.3"
+version = "5.1.16"
 description = "Heartbeat monitoring system — client (hbc) and server (hbd)"
 readme = "README.md"
 requires-python = ">=3.11"
@@ -34,6 +34,9 @@ server = [
   "matrix-nio>=0.24",
 ]
 
+# Minimal client — hbc_mini only, no external dependencies
+mini = []
+
 # Install both client and server
 all = [
   "hbd[client,server]",
@@ -54,6 +57,9 @@ dev = [
 hbd = "hbd.server.cli:main"
 hbc = "hbd.client.main:main"
 
+[tool.setuptools]
+script-files = ["scripts/hb_install.sh", "scripts/hbc_mini.py"]
+
 [tool.setuptools.packages.find]
 where = ["."]
 include = ["hbd*"]

scripts/bumpminor.sh

@@ -4,12 +4,14 @@ set -e
 uv version --bump patch 
 VER=$(uv  version  --short)
 sed -i".bak"  "s/__version__ = \"[0-9.]*\"\(.*\)$/__version__ = \"$VER\"\1/" hbd/__init__.py
+sed -i".bak"  "s/__version__ = \"[0-9.]*\"\(.*\)$/__version__ = \"$VER\"\1/" scripts/hbc_mini.py
 
 # commit pyproject.toml
-git commit -m "version $VER" pyproject.toml hbd/__init__.py
+git commit -m "version $VER" pyproject.toml hbd/__init__.py scripts/hbc_mini.py
 git push 
 # tag version
 git tag -a v$VER -m "Version $VER"
 git push --tags
 
 rm hbd/__init__.py.bak
+rm scripts/hbc_mini.py.bak

scripts/hb_install.sh

@@ -0,0 +1,115 @@
+#!/bin/sh
+
+# Helper script to install the heartbeat tools. By default, it will only
+# install the heartbeat client, hbc. The server is installed when the arg 'server' is passed 
+# to the script. The script will install the heartbeat tools in a python 
+# virtual environment in ~/venvs/hbd. The hbd and hbc commands will be
+# installed from the wheel and symlinked to ~/bin/hbd and ~/bin/hbc,
+# respectively. If the virtual environment already exists, it will be
+# reused. The script will also remove any existing symlinks for hbd and hbc
+# in ~/bin before creating new ones.
+
+set -e
+what=$1
+on_ha=0
+where=""
+venv=""
+[ "$2" = "HA" ] && on_ha=1
+[ -z "$what" ] && what="client"
+
+if [ -d /homeassistant ]; then  # if running from HA command line
+    echo "HA, running \"docker exec homeassistant /config/bin/hb_install.sh $@\""
+    docker exec homeassistant /config/bin/hb_install.sh $@ HA
+    rc=$?
+    if [ $rc -ne 0 ]; then
+        echo "Failed to install heartbeat in HA, please check the logs for more details"
+        exit 1
+    fi
+    exit 0
+fi
+
+if [ $on_ha -eq 1 ] || [ -r /.dockerenv ] && [ -d /config/bin ]; then
+    # Installing under docker on Home Assistant OS, using /config/bin for executables and /config/venvs for virtual environments 
+    echo "Home Assistant OS detected, installing under docker"
+    where="/config/bin"
+    venv="/config/venvs"
+else
+    if [ ! -d $HOME/.local/bin ] && [ ! -d $HOME/bin ]; then
+        echo "No suitable bin directory found in PATH, please add either $HOME/.local/bin or $HOME/bin to your PATH"
+        exit 1
+    fi
+    for where in $HOME/bin $HOME/.local/bin notset ; do
+        if echo ":$PATH:" | grep -q ":$where:" ; then
+            break
+        fi
+    done
+    if [ "$where" = "notset" ]; then
+        echo "No suitable bin directory found in PATH, please add either $HOME/.local/bin or $HOME/bin to your PATH"
+        exit 1
+    fi
+    if [ "$what" = "mini" ]; then
+        venv=""
+    else
+        venv="$HOME/venvs"
+    fi
+fi
+echo "Installing $what to $where"
+if [ ! -z "$venv" ]; then
+    echo "Using virtual environment at $venv/hbd"
+fi
+
+if [ "$venv" != "" ] && [ ! -d  $venv/hbd ]; then
+    arg=""
+    have_pip=$(python3 -c "import pip" 2>/dev/null &> /dev/null && echo "Installed" || echo "Not Installed")
+    if [ "$have_pip" = "Not Installed" ]; then
+        # some systems do not have pip installed by default, so we need to fetch get-pip.py and install pip
+        echo "pip is not installed, fetching get-pip.py and installing pip"
+        arg="--without-pip"
+    fi
+    mkdir -p $venv
+    have_venv=$(python3 -c "import venv" 2>/dev/null &> /dev/null && echo "Installed" || echo "Not Installed")
+    if [ "$have_venv" = "Not Installed" ]; then
+        if [ "$have_pip" = "Not Installed" ]; then
+            echo "python has no venv, and no pip to install virtualenv, cannot continue"
+            exit 1
+        fi
+        echo "python venv module not found, installing virtualenv"
+        python3 -m pip install --user virtualenv
+        python3 -m virtualenv $venv/hbd --system-site-packages $arg
+    else
+        python3 -m venv $venv/hbd --system-site-packages $arg
+    fi
+    . $venv/hbd/bin/activate
+    if [ -n "$arg" ]; then  
+        curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py && python3 get-pip.py
+    fi
+    deactivate
+fi
+
+if [ ! -z "$venv" ]; then
+    . $venv/hbd/bin/activate
+fi
+if [ "$what" = "mini" ]; then
+    curl -s -o $where/hbc_mini https://git.wrede.ca/andreas/heartbeat/raw/branch/master/scripts/hbc_mini.py
+    chmod +x $where/hbc_mini
+else
+    python3 -mpip install --upgrade --index-url https://git.wrede.ca/api/packages/andreas/pypi/simple/ --extra-index-url https://pypi.org/simple hbd[$what]
+fi
+
+if [ ! -z "$venv" ]; then
+    echo "linking executables to $where"
+    if [ "$what" = "server" ]; then
+        rm -f $where/hbd
+        ln -sf $(which hbd) $where/hbd
+    elif [ "$what" = "client" ]; then
+        rm -f $where/hbc
+        ln -sf $(which hbc) $where/hbc
+    fi
+    rm -f $where/hb_install.sh
+    ln -sf $(which hb_install.sh) $where/hb_install.sh
+fi
+echo "Installation complete. To upgrade, run the following:"
+echo "    $where/hb_install.sh $what"
+echo "To install on another machine, run the following obtain the install script and run it:"
+echo "from https://git.wrede.ca/andreas/heartbeat/raw/branch/master/scripts/hb_install.sh"
+echo "and then run sh hb_install.sh [mini|client]"

scripts/install.sh

@@ -1,88 +0,0 @@
-#!/bin/sh
-
-# install the heartbeat client, hbc. The server is installed when the arg 'server' is passed 
-# install the heartbeat client, hbc. The server is installed when the arg 'server' is passed 
-# to the script. The script will install the heartbeat tools in a python 
-# virtual environment in ~/venvs/hbd. The hbd and hbc commands will be
-# installed from the wheel and symlinked to ~/bin/hbd and ~/bin/hbc,
-# respectively. If the virtual environment already exists, it will be
-# reused. The script will also remove any existing symlinks for hbd and hbc
-# in ~/bin before creating new ones.
-
-
-# hbd/hbc from wheel and create symlinks for hbd and hbc in ~/bin
-
-set -e
-what=$1
-on_ha=0
-[ -z "$what" ] && what="client"
-
-if [ -d /homeassistant ]; then
-    echo "cannot install in HA, run \"docker exec -it homeassistant $0 $@\""
-    exit 1
-fi
-if [ -d /config ]; then
-    echo "Installing on HA"
-    where="/config/bin"
-    venv="/config/venvs"
-    on_ha=1
-else
-    if [ ! -d $HOME/.local/bin ] && [ ! -d $HOME/bin ]; then
-        echo "No suitable bin directory found in PATH, please add either $HOME/.local/bin or $HOME/bin to your PATH"
-        exit 1
-    fi
-    for where in $HOME/bin $HOME/.local/bin notset ; do
-        if echo ":$PATH:" | grep -q ":$where:" ; then
-            break
-        fi
-    done
-    if [ "$where" = "notset" ]; then
-        echo "No suitable bin directory found in PATH, please add either $HOME/.local/bin or $HOME/bin to your PATH"
-        exit 1
-    fi
-    venv="$HOME/venvs"
-fi
-
-echo "Installing heartbeat $what"
-
-if [ ! -d  $venv/hbd ]; then
-    python3 -m pip --version > /dev/null 2>&1 
-    if [ $? -ne 0 ]; then
-        # truenas does not have pip installed by default, so we need to fetch get-pip.py and install pip
-        echo "pip is not installed, fetching get-pip.py and installing pip"
-        arg="--without-pip"
-    fi
-    mkdir -p $venv
-    have_venv=$(python3 -c "import venv" &> /dev/null && echo "Installed" || echo "Not Installed")
-    if [ "$have_venv" = "Not Installed" ]; then
-        echo "python venv module not found, installing virtualenv"
-        python3 -m pip install --user virtualenv
-        python3 -m virtualenv $venv/hbd --system-site-packages $arg
-    else
-        python3 -m venv $venv/hbd --system-site-packages $arg
-    fi
-    . $venv/hbd/bin/activate
-    if [ -n "$arg" ]; then  
-        curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py && python3 get-pip.py
-    fi
-    deactivate
-fi
-
-. $venv/hbd/bin/activate
-python3 -mpip install --upgrade --index-url https://git.wrede.ca/api/packages/andreas/pypi/simple/ --extra-index-url https://pypi.org/simple hbd[$what]
-
-if [ "$what" = "server" ]; then
-    rm -f $where/hbd
-    ln -sf $(which hbd) $where/hbd
-    echo "hbd installed, you can run it with \"$where/hbd\" or \"hbd\" if $where is in your PATH"
-else
-    rm -f $where/hbc
-    ln -sf $(which hbc) $where/hbc
-    if [ $on_ha -eq 1 ]; then
-        echo "restarting hbc "
-        job=$(grep run_hbc configuration.yaml | sed 's/run_hbc://')
-        $job
-    else
-        echo "hbc installed, you can run it with \"$where/hbc\" or \"hbc\" if $where is in your PATH"
-    fi  
-fi