Incus/IncusOS and OCI console logging

1

I’ve been slowly working through the process of using OCI images in Incus/OS (thanks to all involved in helping there!) and have come to the issue of logging.

Quite a few of my container images log to stdout/stderr (eg https://hub.docker.com/\_/nginx ), so i need to be able to query those logs over time.

incus console ... --show-log (as suggested in Obtaining container logs on IncusOS ) is ok for ad hoc queries but

  • once the logs are read, they aren’t repeated (its not like running tail on a file)
  • if there are too many logs nothing is displayed at all.

I’m developing with Incus+Debian but the hosting environment is IncusOS, so looking at the on disk files (as suggested in How to show logs from OCI container or where to find them? - #5 by cstby ) isn’t feasible once moving beyond the hacking around stage.

Will IncusOS store those instance console logs long term somewhere I can gather them or will I have to enable syslog ( Logging - IncusOS documentation ) so those console logs are streamed to a log sink?

Can Incus-on-Debian be configured to record those console logs via syslog/systemd to better help emulate the incusos hosting environment?

2

There has been a fix in 7.2 where the ringbuffer doesn’t get reseted, so you should be able to call --show-log multiple times.

But it is a ringbuffer so it’s output might not be determistic.

I’ve been thinking with incus-compose about the same problem you describe and I think we should add support for something like fluentd as log collector.

3

I’m on IncusOS 202606201302 so may not have picked up that fix yet, I’ll look at updating to at least solve that bit of the problem.

While investigating this issue (before posting) I found Configurable syslog targets · Issue #1420 · lxc/incus · GitHub which mentions Loki logging. For me it shares a problem with syslog - I’d need to deploy another service to ingest those logs (I will if thats the only option, of course!)

Something inside IncusOS that would have allowed the equivalent of tail /var/log/incus/container-*/console.log would have been handy if it existed.