Tier 2 rsync-mirrors each HDD app's recovery unit + appdata to a DIFFERENT physical
disk (the only off-drive protection bind-mounted userdata can get; PBS can't reach it).
Auto-enabled, auto-target: prefer another registered drive (different physical disk via
system.SamePhysicalDevice), else the internal SSD for SMALL units only — with a
size-aware headroom guard that REFUSES rather than fill the ~8G guest rootfs, recording
an honest "needs 2nd HDD" status. Status persisted via the surviving CrossDriveBackup;
"2. mentés" UI card now populated. Daily tier2-backup job + POST /api/backup/tier2.
- backup/tier2.go (engine+selection+headroom), tier2_test.go (headroom arithmetic)
- system.SamePhysicalDevice (linux Stat_t.Dev + stub)
- handlers.go Tier2 UI population + tier2DestLabel; backups.html honest no-target reason
- fixed stale TestBackupCopiesOnPath (old felhom-data layout -> in-guest layout)
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
CaptureRecoveryUnit now builds content in memory and skips writes when the unit
is already current (checksum + dump-set + version), so it can run from RefreshCache
(startup + every 5m) without thrashing the USB drive. Units now exist shortly after
startup and track config changes without waiting for the daily DB dump. +idempotency test.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>