systemd applies WorkingDirectory= to every Exec line including ExecStartPre.
With the merged dir not yet existing at boot time (the volatile overlay
mount has been wiped), the chdir into runtime/%i/merged/left4dead2 fails
with status=200/CHDIR before ExecStartPre can run the mount helper.
The `-` prefix makes chdir failure non-fatal: ExecStartPre runs in the
unit's home (cwd doesn't matter for the mount helper); ExecStart re-applies
WorkingDirectory once the mount has landed and chdirs successfully.
Companion to commit 519567e (which added the ExecStartPre mount + helper
idempotency but didn't account for the WorkingDirectory ordering).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The lifecycle change to systemctl enable --now (commit 8552c55) made
units auto-start at boot. But the kernel-overlayfs mount is volatile
(reboot kills it), and the web app's start_instance only re-mounts in
response to a UI click. Result: at boot, systemd starts the unit, finds
empty merged/, CHDIR fails, Restart=on-failure spins forever (counter
hit 65 on ckn before this fix landed).
Fix:
- Unit gets `ExecStartPre=/usr/bin/sudo -n .../left4me-overlay mount %i`
so the overlay is established before the main process starts.
- Helper is now idempotent: if merged is already a mount point, exit 0.
Required because Restart=on-failure re-runs ExecStartPre on each
cycle, and the web-app's start_instance also calls the helper, so
both paths would otherwise collide on "already mounted".
- StartLimitBurst=5 + StartLimitIntervalSec=60s caps the restart loop
instead of letting it spin indefinitely on a fundamental failure.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
