Container Layout

/data
 ├─ config.yaml           # See also configuration reference
 ├─ logs/                 # Rolling logs for agent, every data flow, Redpanda …
 ├─ redpanda/             # Redpanda data & WALs (backup-worthy)
 └─ hwid                  # Device fingerprint sent to the console

Mount one persistent volume (e.g. umh-core-data) to /data and you’re done.

/config.yaml

See also Configuration Reference

/logs

File/dir	What it is for	When it appears
current	The file S6 is actively appending log lines to. Keep an eye on this one with tail -f.	Always – it is recreated immediately after every rotation. (Skarnet)
previous	A temporary name used during a rotation; disappears once rotation completes.	Only while a rotation is in flight. (Skarnet)
@<timestamp>.s	An archived log that was rotated cleanly. The timestamp is the moment the rotation occurred.	After every successful rotation. (Skarnet)
@<timestamp>.u	A “unfinished” archive – it was the current file when the container was killed.	Only after an un-clean shutdown. (Skarnet)
lock, state, processed, newstate	Book-keeping files S6-log uses while rotating or while a post-processor runs.	Internal – you normally ignore them. (Skarnet)

The life-cycle in practice

1. Normal running – all services write to their own current file.

2. Size hits 1 MB – S6 atomically renames current to a name such as @20250530T131218Z.s, then immediately creates a fresh empty current. (Skarnet)

3. Prune – if the directory now has > 20 archives, the oldest ones are deleted so the newest 20 remain. (Skarnet)

4. You read logs – use:

   # live stream
   tail -f /data/logs/<service>/current
   
   # inspect an old file (the '@…s' ones are plain text)
   less /data/logs/<service>/@20250530T131218Z.

/redpanda

The Redpanda data directory.

HWID

A unique identifier for that UMH Core installation. Useful for troubleshooting.