/var/lib/ci/backups was root:root because ci-backup-template.service
runs as root and mkdir(exist_ok=True) created it before ci-runner ever
touched it, so every 7z backup failed with errno=13. Chown to
ci-runner:ci-runner + 750, and stop the drift from coming back: the
setup script now creates+chmods the dir, and the systemd unit gets an
ExecStartPre that (re)installs it with the right owner on every start.
Backups had grown to 195 GB -- half the disk, which was at 94% -- because
retention run covers only artifacts, logs and IP leases, none of which weigh
anything here. The three generations were byte-identical per template: the
templates rarely change, so the extra copies bought nothing. WinBuildTest alone
cost 26 GB per generation and has been unused since 2026-06-10.
If ci-backup-template.service is killed mid-run (SIGTERM), the Python
finally block that restarts act-runner.service is skipped. A subsequent
backup then finds the runner already inactive, _stop_runner returns
False, and the finally restart is gated off — leaving the runner down
indefinitely (incident: 21 mag 2026, runner stayed off ~80 min).
Add ExecStopPost=-/bin/systemctl start act-runner.service so systemd
guarantees the runner is restarted regardless of how the unit exits
(success, failure, signal). The `-` prefix preserves the unit's own
exit status.
- Add `retention run` command (ports Invoke-RetentionPolicy.ps1): purges
old artifact/log dirs with aggressive mode when disk space is low.
- Add `template backup` command (ports Backup-CITemplate.ps1): 7z -mx=1
compressed archives in /var/lib/ci/backups/, prunes to keep-count=3,
stops/restarts act-runner.service around the copy.
- Update ci-retention-policy.service and ci-backup-template.service to use
Python; pwsh is no longer required on the Linux host.
- Fix ci-watch-runner-health.service: pass --service-name act-runner
(Linux service name, not Windows act_runner default).
- Fix _list_orphans in vm.py: wrap is_dir() inside the OSError try block
so a stat() failure on an entry is silently skipped rather than raised.
- Mark B5 complete in PhaseB-user-checklist.md.
Simone