rdmsm4x-changelog-20260913-2150-timemachine-unaspro818-udm-dns-fix

Summary: Time Machine on rdmsm4x had not backed up since 2026-09-02. A ghost client on the UDM served unaspro818a → a dead IP, and automatic backups were switched off. Fixed the UDM DNS records and re-enabled TM. The first backup completed 2026-09-14 08:16 EDT (RESULT=0).

Hosts: rdmsm4x (Time Machine); UDM udmdataroonet 192.168.1.1 (DNS)
Window: 2026-09-13 21:34:33 EDT → 2026-09-14 08:16:25 EDT

Cause

The UDM client table held a ghost client: MAC 46:10:25:d8:01:43 (randomized), named unaspro818a, last seen 2026-04-22, with Local DNS Record unaspro818a.local → 192.168.1.8. That address is dead.
The Mac's DNS search list includes local ahead of dataroo.net, so the bare name unaspro818a in the TM URL smb://rich@unaspro818a/timemachine got the dead IP. backupd: NAConnectToServerSync failed with error: 60.
The real NAS port-1 record had a typo: unaspro8a.18a.dataroo.net.
AutoBackup = 0 in /Library/Preferences/com.apple.TimeMachine.

Changes

Where	Change
UDM mongo `ace.user` 46:10:25:d8:01:43	`local_dns_record_enabled` true→false; name marked GHOST
UDM mongo `ace.user` 8c:30:66:c4:65:24 (192.168.0.9)	`local_dns_record` `unaspro8a.18a.dataroo.net` → `unaspro818a.dataroo.net`
UDM mongo `ace.user` 8c:30:66:c4:65:25 (192.168.1.5)	added `unaspro818.dataroo.net` (enabled)
UDM	`systemctl restart unifi` (Network app only; dnsmasq re-rendered in 5s)
rdmsm4x	`sudo tmutil enable`; `sudo tmutil startbackup --auto`
`~/dev/net/fleet-netmgmt/docs/findings.md`	new 2026-09-13 section, commit `1c8c05b`

Verification

UDM, Tailscale 100.100.100.100 and dscacheutil all return unaspro818 → 192.168.1.5 and unaspro818a → 192.168.0.9. unaspro818a.local now comes only from mDNS (.0.9/.1.5). TCP 445 is open on both names.
backupd mounted /Volumes/Backups of rdmsM4m, passed HealthCheckFsck and reached FindingChanges (12,001 items) by 21:47 EDT.
Progress 2026-09-14 05:48 EDT: Copying, 71% (624 GB of 4.86 TB scope; 2.82M of 23.6M files). Rate over the last 2h was ~100-220 GB/h; backupd estimated ~3.2h remaining. Copy finished ~07:22 EDT, thinning ran until 08:16 EDT.
Completed 2026-09-14 08:16 EDT: tmutil latestbackup = 2026-09-14-072234.backup, RESULT = 0, AutoBackup = 1, Running = 0. Elapsed about 10.5h for the catch-up backup.

Backups / undo

UDM /data/backup-claude/user-unas-dns-20260913-214451.jsonl holds the original 3 client docs. /data/backup-claude/dnsmasq-main-20260913-214451.conf is the rendered config before the change.
Undo: mongo --port 27117 ace, db.user.updateOne each MAC back to the jsonl values, then systemctl restart unifi. TM: sudo tmutil disable.

Outstanding

Rich's UniFi OS login returned 403 SSO Account locked from the local API. That lockout predates any fix here. Clear it in the UniFi UI/account if it is unexpected.
Plaintext modem password in apps/DishTTY/SESSION-STATE.md → routed as ~/dev/todo/items/20260913-dishtty-plaintext-modem-password.md.