Where are the Hassio Addon logs stored?

To be clear, I already understand that I can view the logs through the frontend by clicking on the addon of interest. However, I would like to tail the logs in a separate log viewing program to make it easier to filter and view human-readable timestamps for the purposes of debugging.

The log I am interested in right now is the embedded mosquito broker. Considering that I am using hassio, is it possible for me to access that log file via SSH or SAMBA?

4 Likes

did you come to a solution?

I am working on a few plugins and thinking of setting up logging of the applications that run in the containers to output to a /share/logs/appx folder.
Maybe also work on a separate that would manage these logs (rotate/prune/archive/consolidate) and provide a web based viewer.

This seems like more of a framework capability that hassio should provide.

I would like to know that too

Hey, Im having same problem, have u found addons logs?

My apologies for the late reply, but I have not found how to access the addon logs externally.

Looking at my containers, it looks like add-ons use journald logging. You can use journalctl to view them from the host, but you can also just use docker logs.

As far as I can tell, they’re not saved to a file anywhere. You could potentially write an add-on that has access to the host docker (see the Portainer add-on for an example) and use that to dump the logs to a file somewhere.

There are some files under /var/log/journal but I’m on my phone and can’t check them right now.

3 Likes

I use the standard Raspberry Pi SD card image installation method of Hassio. Can journalctl be used with that, and if so, how does one go about it?

I would assume so if it’s running HassOS but I’m not 100% sure. For journalctl, you need access to the host.

I have it running on Proxmox so I’m not sure if it’s the same on the Pi, but I get a terminal on the device (probably just plug in a keyboard and monitor to the Pi?), username is root to get to the Hassio command line, then type login and it will drop you into a terminal on the host.

However, for docker logs you can probably do it through the community SSH add-on by disabling protection mode, which gives it access to the host Docker.

I just confirm it.

Based on docker inspect ..., add-ons are using the host’s journald.

But there is no journalctl in the ssh add-on.

So you have to ssh into the host, and there you can use sg. like journalctl CONTAINER_NAME=addon_... Use sg. like docker ps to see the add-on’s container names.

This way you can see into the past and you can see the logs of stopped add-ons also. Cool.

Does this work with HASS OS?

Yes, works, absolutely. Tested now with OS 9.3.

Though you have to ssh into the host, not into the ssh add-on (what is a docker container only), see: Debugging the Home Assistant Operating System | Home Assistant Developer Docs

As of supervisor version 2022.10.2 the /api/host/logs endpoint allows clients to interface directly with the system journal via supervisor. You can make calls to this endpoint from the cli by doing ha host logs. It doesn’t have all the options of journalctl but it has enough to cover this use case. To see logs for a particular addon you can do this:

ha host logs --identifier addon_core_mosquitto

Replace core_mosquitto with the slug of the addon you want to see logs for. The only kind of gotcha is that you have to prefix the addon slug with addon_ since it has to be the docker container name.

You can also limit the results to a specific number of rows, specific boot of the machine and tail with the other options:

> ha host logs -h
Allows you to look at the systemd journal on the host to see logs
across services and boots.
Usage:
  ha host logs [flags]
  ha host logs [command]
Aliases:
  logs, log, lg
Examples:
  ha host logs
Available Commands:
  boots       Show all boot IDs by offset
  identifiers Show all syslog identifiers
Flags:
  -b, --boot string         Logs of particular boot ID
  -f, --follow              Continuously print new log entries
  -h, --help                help for logs
  -t, --identifier string   Show entries with the specified syslog identifier
  -n, --lines int32         Number of log entries to show

This can all be done from the ssh or vscode addons without going directly to the host shell.

2 Likes

Interesting!! Makes sense

Amazing, this made it very simple. Thanks!