Server Monitor

A mobile app for monitoring server metrics & status information in real-time.

The front-end client is a modern Material 3 Android application written in Kotlin for displaying, and the back-end server service is a .NET Core 7.0 console application written in C# that acts as either a RESTful API or a Prometheus metrics exporter.

🖼️ Screenshots

📥 Usage

A Prometheus time-series database is required for storing the metrics data. Additionally, a Cloudflare Tunnel (or other secure HTTP tunnel) is highly recommended to expose the RESTful API service to the Internet, allowing secure access to it from the Android application.

1. Download the latest release of the Android application (ServerMonitor-App.zip) & server service (ServerMonitor-Service.zip).
2. Install the server service on all the servers you wish to manage (the .NET Core 7.0 Runtime is required).
   • One server must be designated as the "connector" (RESTful API) for the Android application to fetch metrics data from. See Connector.
   • All other servers must run in the "collection" mode for gathering & exporting metrics data for Prometheus to scrape. See Collector.
3. Configure the server service appropriately using the JSON configuration file or environment variables (see configuration).
4. Install the Android application on your device & connect to the publicly-accessible URL of the "connector" service using any of the configured credentials.

🐳 Docker

Alternatively, a premade Docker image of the back-end server service is available to simplify the process of deployment.

Download & start the "collector" by running the following command:

docker container run \
	--name server-monitor-collector \
	--mount type=bind,source=/path/to/your/config.json,target=/etc/server-monitor/config.json \
	--mount type=bind,source=/etc/systemd,target=/etc/systemd \
	--mount type=bind,source=/var/lib/systemd,target=/var/lib/systemd \
	--mount type=bind,source=/usr/lib/systemd,target=/usr/lib/systemd \
	--mount type=bind,source=/run/systemd,target=/run/systemd \
	--mount type=bind,source=/run/dbus/system_bus_socket,target=/run/dbus/system_bus_socket \
	--network host \
	--privileged \
	--user 0:0 \
	--restart on-failure \
	--pull always \
	ghcr.io/viral32111/server-monitor:main-ubuntu
	collector

• Use the :main-windows image tag for Windows-based Docker installations.
• Remove all the systemd & dbus mounts when running on Windows-based Docker installations.
• The JSON configuration file should be mounted at /etc/server-monitor/config.json.
• By default the Prometheus metrics exporter uses port 5000, and the action server uses port 6997.

Download & start the "connector" by running the following command:

docker container run \
	--name server-monitor-connector \
	--mount type=bind,source=/path/to/your/config.json,target=/etc/server-monitor/config.json \
	--publish published=127.0.0.1:6996,target=6996,protocol=tcp \
	--restart on-failure \
	--pull always \
	ghcr.io/viral32111/server-monitor:main-ubuntu
	connector

• Use the :main-windows image tag for Windows-based Docker installations.
• The JSON configuration file should be mounted at /etc/server-monitor/config.json.
• By default the RESTful API uses port 6996.

NOTE: Some features of the Docker image in "collector" mode are tedious on some systems due to availability of system API functions, especially on Windows-based Docker installations. It is recommended to only use the Docker image for the "connector" mode, then a regular installation for the "collector" mode.

⚙️ Configuration

The JSON configuration file is searched for at the following paths:

• Windows
  • System: C:\ProgramData\ServerMonitor\config.json
  • User: C:\Users\USERNAME\AppData\Local\ServerMonitor\config.json
• Linux
  • System: /etc/server-monitor/config.json
  • User: /home/USERNAME/.config/server-monitor/config.json

Alternatively, a path to a configuration file in a non-standard location can be specified with the --config <path> option (use --help for more information).

Configuration properties can also be set via environment variables prefixed with SERVER_MONITOR_.

The configuration priority is as follows (higher entries will override previously configured properties):

1. Environment variables.
2. Non-standard configuration file (--config <path> option).
3. User-specific configuration file.
4. System-wide configuration file.

See config.json for an example configuration file.

💿 Modes

🖥️ Collector

This mode exports metrics from configured sources for Prometheus to scrape.

Either start the service with the collector command-line argument, or register a new system service using a command below.

On Windows, run the following PowerShell command to create a new service, ensuring to replace the .NET Core Runtime & application paths where appropriate.

New-Service -Name "Server-Monitor-Collector" -DisplayName "Server Monitor (Collector)" -Description "Export metrics to Prometheus from configured sources." -BinaryPathName '"C:\Path\To\Dotnet\Runtime\dotnet.exe" "C:\Path\To\ServerMonitor\ServerMonitor.dll" --service collector' -StartupType "Automatic" -DependsOn "LanmanServer"

On Linux (for systemd), firstly create a new service file at /etc/systemd/service/server-monitor-collector.service with the following contents.

[Unit]
Description=Server Monitor (Collector)
Documentation=https://github.com/viral32111/ServerMonitor
After=network.target

[Service]
User=root
Group=root
WorkingDirectory=/path/to/servermonitor
ExecStart=/path/to/dotnet /path/to/servermonitor/ServerMonitor.dll --service collector
Type=simple
Restart=on-failure

[Install]
WantedBy=multi-user.target

Then run systemctl daemon-reload to reload service files, followed by systemctl enable server-monitor-collector so the service launches on system startup.

🛰️ Connector

This mode serve metrics from Prometheus to the Android app via a RESTful API.

Either start the service with the connector command-line argument, or register a new system service using a command below.

On Windows, run the following PowerShell command to create a new service, ensuring to replace the .NET Core Runtime & application paths where appropriate.

New-Service -Name "Server-Monitor-Connector" -DisplayName "Server Monitor (Connector)" -Description "Serve metrics from Prometheus to the Android app." -BinaryPathName '"C:\Path\To\Dotnet\Runtime\dotnet.exe" "C:\Path\To\ServerMonitor\ServerMonitor.dll" --service connector' -StartupType "Automatic" -DependsOn "LanmanServer"

On Linux (for systemd), firstly create a new service file at /etc/systemd/service/server-monitor-connector.service with the following contents.

[Unit]
Description=Server Monitor (Connector)
Documentation=https://github.com/viral32111/ServerMonitor
After=network.target

[Service]
User=root
Group=root
WorkingDirectory=/path/to/servermonitor
ExecStart=/path/to/dotnet /path/to/servermonitor/ServerMonitor.dll --service connector
Type=simple
Restart=on-failure

[Install]
WantedBy=multi-user.target

Then run systemctl daemon-reload to reload service files, followed by systemctl enable server-monitor-connector so the service launches on system startup.

To verify service existence on Windows, open the Services (services.msc) application and check for the two "Server Monitor" services, it should be similar to the screenshot below.

🏗️ Building

App

1. Create a key store & signing key, then configure signing using environment variables or the global Gradle configuration file (~/.gradle/gradle.properties).
   • Alternatively remove the signing configuration from the Gradle build file to disable APK signing.
2. Build the Android application with Gradle by running ./gradlew assembleRelease in the App directory.
3. Optionally run instrumented tests by running ./gradlew test in the App directory.

The APK file will be created at App/app/build/outputs/apk/release/app-release.apk.

Service

1. Add https://nuget.pkg.github.com/viral32111/index.json as a NuGet packages source, as one of the dependencies is my JSON Extensions package.
2. Build the server service with .NET by running dotnet build --configuration Release in the Service directory.
3. Optionally run unit & integration tests by running dotnet test --configuration Release in the Service directory.

The resulting DLL file & dependencies will be created at Service/ServerMonitor/bin/Release/net7.0/ServerMonitor.dll.

✔️ Progress

There is a Kanban board that uses the issues for tracking progress on individual steps of the project.

There are also dated milestones which correspond to the stage completion dates from initial Gantt chart.

See the releases page for minimum-viable products from most stages/tasks.

⚖️ License

This project is licensed under the Creative Commons Attribution-ShareAlike 4.0 International license, see the license file for more information.