Uptime Kuma reports DOWN, but the service can be accessed
If your Uptime Kuma reports DOWN of your service, knowing if it is a bug of Uptime Kuma / a docker network misconfiguration or a firewall is a good start to fixing the issue.
To debug this, go into your container's bash via
Install curl
Then you can debug this issue with commands like ping, curl, ... Examples:
IPv6
If you are running Uptime Kuma on top of Docker and the service can only be access via IPv6. Please follow the Docker's official wiki to enable IPv6 support.
IPv6 are not supported out of the box on Docker.
For docker compose, this is as simple as adding a network with IPv6 enabled to your compose file. Upating the template from the project would look like this:
The network is created at the bottom, with enable_ipv6: true and then added to the service.