How-to-Monitor-Docker-Containers.md

(Version >= 1.18.0)

If you are running Uptime Kuma Docker

By default, a docker container is self-contained, which means Uptime Kuma cannot access your host. You need to bind the /var/run/docker.sock to your container.

(Method 1) Share docker.sock with Uptime Kuma Container

Command argument:

-v /var/run/docker.sock:/var/run/docker.sock

docker-compose:

volumes:
   - /var/run/docker.sock:/var/run/docker.sock

(Method 2) TCP - Bridge Mode

Expose TCP port
To enable TCP monitoring, you need to first expose the Docker daemon on a TCP port. The primary documentation is available here but the example below provides some quick options.

Update the daemon configuration located at /etc/docker/daemon.json:

{
   #any additional parameters should be kept

   #Insecure option, only use this if you are running on a closed network
   "hosts": ["unix:///var/run/docker.sock", "tcp://<host IP address>:2375"]

   #Secure option
   "tls": true,
   "tlscert": "/var/docker/server.pem",
   "tlskey": "/var/docker/serverkey.pem",
   "hosts": ["unix:///var/run/docker.sock", "tcp://<host IP address>:2376"]
}

Restart the daemon using sudo systemctl restart docker.service.

If the daemon fails to start, it may be because there are duplicate keys, in this case hosts, -H, that is already part of the daemon configuration.

You can edit the startup configuration using sudo systemctl edit docker.service.

[Service]
#The blank ExecStart is required to clear the current entry point
ExecStart=
#Replace the existing ExecStart but only remove the properties that you have added into the daemon.json file, leave all else the same.
ExecStart=/usr/bin/dockerd --containerd=/run/containerd/containerd.sock

My original ExecStart was: ExecStart=/usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock, note the -H that would cause a duplicate property error.

Note

If you installed docker using snap

Snap stores the daemon.json here: /var/snap/docker/current/config/daemon.json

use sudo nano /var/snap/docker/current/config/daemon.json to edit the file like

{
    "log-level":        "error",
    "storage-driver":   "overlay2",
+   "hosts": ["unix:///var/run/docker.sock", "tcp://0.0.0.0:2375"]
}

• Restart the service using sudo systemctl restart snap.docker.dockerd.service
• Check if the service is running using sudo systemctl status snap.docker.dockerd.service

The service should be running as usual, showing the docker snap service

Update uptime-kuma
Add a new Docker host and choose TCP as the option. Specify the IP address of the host and the TCP port you exposed, as seen below.

Related Discussion

• louislam/uptime-kuma#2061