La copia de seguridad de Time Machine falla silenciosamente. El registro dice "Copia de seguridad cancelada".

Desde hace unos días, la mayoría de los intentos de Time Machine de hacer una copia de seguridad de mi Mac se cancelan silenciosamente. La situación es la siguiente:

• Las copias de seguridad automáticas de Time Machine están activadas.
• La preparación de las copias de seguridad se inicia de forma programada, como puede verse al hacer clic en el elemento de la barra de menús de Time Machine.
• El procedimiento de respaldo se cancela sin previo aviso.

La última copia de seguridad realizada con éxito tiene ya 48 horas, aunque mi Mac ha estado en casa todo el día y ha tenido muchas posibilidades de hacer una copia de seguridad.

Estoy en 10.14.2. Utilizo una Time Capsule MB277 de 2008 o 2009 a través de WiFi. Esta es la salida del syslog relacionada con Time Machine de un intento fallido de hacer una copia de seguridad manual de mi máquina:

MacBook-Air-3:~ xxx$ log stream --style syslog  --predicate 'senderImagePath contains[cd] "TimeMachine"' --info
Filtering the log data using "senderImagePath CONTAINS[cd] "TimeMachine""
Timestamp                       (process)[PID]    
2019-01-29 17:42:58.119096+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Starting manual backup
2019-01-29 17:42:58.123368+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Destination Backups could not be found (url: (null) destinationID: 14938BA8-FAA4-47F2-9E2D-2C50C921FA93)
2019-01-29 17:42:58.129234+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogError] Backup failed with error 18: The backup disk could not be found.
2019-01-29 17:42:58.155071+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Starting manual backup
2019-01-29 17:42:58.374462+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Attempting to mount 'afp://xxx;AUTH=SRP@Time%20Capsule._afpovertcp._tcp.local./Time%20Capsule'
2019-01-29 17:42:59.364160+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Mounted 'afp://xxx;AUTH=SRP@Time%20Capsule._afpovertcp._tcp.local./Time%20Capsule' at '/Volumes/com.apple.TimeMachine.Time Capsule-5E757F80-34D5-43A7-B4CB-7D2D9078DF8A'
2019-01-29 17:43:00.197845+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Checking size of '/Volumes/com.apple.TimeMachine.Time Capsule-5E757F80-34D5-43A7-B4CB-7D2D9078DF8A/MacBook Air (4).sparsebundle'
2019-01-29 17:43:13.729070+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Checking for runtime corruption on '/Volumes/com.apple.TimeMachine.Time Capsule-5E757F80-34D5-43A7-B4CB-7D2D9078DF8A/MacBook Air (4).sparsebundle'
2019-01-29 17:43:16.458494+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Runtime corruption check passed for '/Volumes/com.apple.TimeMachine.Time Capsule-5E757F80-34D5-43A7-B4CB-7D2D9078DF8A/MacBook Air (4).sparsebundle'
2019-01-29 17:43:16.609785+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Ejected disk2 from '/Volumes/com.apple.TimeMachine.Time Capsule-5E757F80-34D5-43A7-B4CB-7D2D9078DF8A/MacBook Air (4).sparsebundle'
2019-01-29 17:43:21.242322+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] '/Volumes/com.apple.TimeMachine.Time Capsule-5E757F80-34D5-43A7-B4CB-7D2D9078DF8A/MacBook Air (4).sparsebundle' mounted at '/Volumes/Time Machine-Backups'
2019-01-29 17:43:22.620336+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Backing up to /dev/disk2s2: /Volumes/Time Machine-Backups/Backups.backupdb
2019-01-29 17:43:30.734411+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogError] Failed to remove attribute 'com.apple.backupd.SnapshotVolumeFSEventStoreUUID' from 'file:///', error: Error Domain=NSPOSIXErrorDomain Code=1 "Operation not permitted"
2019-01-29 17:43:30.734708+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogError] Failed to remove attribute 'com.apple.backupd.SnapshotVolumeLastFSEventID' from 'file:///', error: Error Domain=NSPOSIXErrorDomain Code=1 "Operation not permitted"
2019-01-29 17:43:30.735162+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogError] Failed to remove attribute 'com.apple.backupd.SnapshotVolumeUUID' from 'file:///', error: Error Domain=NSPOSIXErrorDomain Code=1 "Operation not permitted"
2019-01-29 17:43:30.735327+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogError] Failed to remove attribute 'com.apple.backupd.PreviousSnapshotVolumeUUID' from 'file:///', error: Error Domain=NSPOSIXErrorDomain Code=1 "Operation not permitted"
2019-01-29 17:43:30.739730+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogError] Failed to remove attribute 'com.apple.backupd.PreviousSnapshotVolumeName' from 'file:///', error: Error Domain=NSPOSIXErrorDomain Code=1 "Operation not permitted"
2019-01-29 17:43:30.739943+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogError] Failed to remove attribute 'com.apple.backupd.VolumeBytesUsed' from 'file:///', error: Error Domain=NSPOSIXErrorDomain Code=1 "Operation not permitted"
2019-01-29 17:43:30.740102+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogError] Failed to remove attribute 'com.apple.backupd.VolumeIsCaseSensitive' from 'file:///', error: Error Domain=NSPOSIXErrorDomain Code=1 "Operation not permitted"
2019-01-29 17:43:30.740257+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogError] Failed to remove attribute 'com.apple.backupd.fstypename' from 'file:///', error: Error Domain=NSPOSIXErrorDomain Code=1 "Operation not permitted"
2019-01-29 17:43:30.740409+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogError] Failed to remove attribute 'com.apple.backupd.VolumeIsEncrypted' from 'file:///', error: Error Domain=NSPOSIXErrorDomain Code=1 "Operation not permitted"
2019-01-29 17:43:31.351366+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Starting age based thinning of Time Machine local snapshots on disk '/'
2019-01-29 17:43:31.474925+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Skipping age based thinning of Time Machine reference snapshot 'com.apple.TimeMachine.2019-01-28-001417' on disk '/'
2019-01-29 17:43:42.350366+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Space based purging deleted Time Machine local snapshot 'com.apple.TimeMachine.2019-01-29-174115' on disk '/ in 56.4 seconds' - current free space: 6,58 GB (6.579.822.592 Byte), target free space: 14,87 GB (14.865.887.232 Byte), initial free space: 6,57 GB (6.566.518.784 Byte)
2019-01-29 17:43:42.358801+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Completed space based purging of snapshots on disk '/' in 56.5 seconds - current free space: 6,58 GB (6.579.822.592 Byte), target free space: 14,87 GB (14.865.887.232 Byte), initial free space: 6,57 GB (6.566.518.784 Byte), urgency: 3, remaining snapshots: (
    "com.apple.TimeMachine.2019-01-28-001417"
)
2019-01-29 17:43:42.365949+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogError] Failed to write unlock record UUIDs as extended attribute for disk '/', error: Error Domain=NSPOSIXErrorDomain Code=1 "Operation not permitted"
2019-01-29 17:43:43.243737+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Created Time Machine local snapshot with name 'com.apple.TimeMachine.2019-01-29-174342' on disk '/'
2019-01-29 17:43:43.250191+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Declared stable snapshot: com.apple.TimeMachine.2019-01-29-174342
2019-01-29 17:43:44.253895+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Mounted stable snapshot: com.apple.TimeMachine.2019-01-29-174342 at path: /Volumes/com.apple.TimeMachine.localsnapshots/Backups.backupdb/MacBook Air (4)/2019-01-29-174342/Macintosh HD source: Macintosh HD
2019-01-29 17:43:44.265663+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Mounted reference snapshot: com.apple.TimeMachine.2019-01-28-001417 at path: /Volumes/com.apple.TimeMachine.localsnapshots/Backups.backupdb/MacBook Air (4)/2019-01-28-001417/Macintosh HD source: Macintosh HD
2019-01-29 17:47:15.597633+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Will copy (2,32 GB) from Macintosh HD
2019-01-29 17:47:15.605699+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Found 23055 files (2,32 GB) needing backup
2019-01-29 17:47:16.048845+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] 7,72 GB required (including padding), 485,82 GB available
2019-01-29 17:47:47.476452+0100  localhost backupd-helper[69]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Not starting scheduled Time Machine backup: Backup already running
2019-01-29 17:50:50.519614+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Starting space based purging of local snapshots on disk '/' - current free space: 6,47 GB (6.474.358.784 Byte), target free space: 14,82 GB (14.817.628.979 Byte), initial free space: 6,47 GB (6.474.358.784 Byte), urgency: 1
2019-01-29 17:50:50.520324+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Starting age based thinning of Time Machine local snapshots on disk '/'
2019-01-29 17:50:50.521321+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Skipping age based thinning of Time Machine reference snapshot 'com.apple.TimeMachine.2019-01-28-001417' on disk '/'
2019-01-29 17:50:50.521873+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Space based purging skipped Time Machine dataless reference snapshot 'com.apple.TimeMachine.2019-01-28-001417' on disk '/'
2019-01-29 17:50:50.522128+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Space based purging skipped Time Machine stable snapshot 'com.apple.TimeMachine.2019-01-29-174342' on disk '/'
2019-01-29 17:50:50.528323+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Completed space based purging of snapshots on disk '/' in 0.0 seconds - current free space: 6,47 GB (6.474.358.784 Byte), target free space: 14,82 GB (14.817.628.979 Byte), initial free space: 6,47 GB (6.474.358.784 Byte), urgency: 1, remaining snapshots: (
    "com.apple.TimeMachine.2019-01-28-001417",
    "com.apple.TimeMachine.2019-01-29-174342"
)
2019-01-29 17:50:52.495903+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Starting space based purging of local snapshots on disk '/' - current free space: 6,47 GB (6.473.363.456 Byte), target free space: 14,82 GB (14.816.633.651 Byte), initial free space: 6,47 GB (6.473.363.456 Byte), urgency: 2
2019-01-29 17:50:52.496671+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Starting age based thinning of Time Machine local snapshots on disk '/'
2019-01-29 17:50:52.497723+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Skipping age based thinning of Time Machine reference snapshot 'com.apple.TimeMachine.2019-01-28-001417' on disk '/'
2019-01-29 17:50:52.498287+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Space based purging skipped Time Machine dataless reference snapshot 'com.apple.TimeMachine.2019-01-28-001417' on disk '/'
2019-01-29 17:50:52.498577+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Space based purging skipped Time Machine stable snapshot 'com.apple.TimeMachine.2019-01-29-174342' on disk '/'
2019-01-29 17:50:52.504812+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Completed space based purging of snapshots on disk '/' in 0.0 seconds - current free space: 6,47 GB (6.473.363.456 Byte), target free space: 14,82 GB (14.816.633.651 Byte), initial free space: 6,47 GB (6.473.363.456 Byte), urgency: 2, remaining snapshots: (
    "com.apple.TimeMachine.2019-01-28-001417",
    "com.apple.TimeMachine.2019-01-29-174342"
)
2019-01-29 17:51:17.367399+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Starting space based purging of local snapshots on disk '/' - current free space: 6,46 GB (6.462.078.976 Byte), target free space: 15,02 GB (15.021.101.056 Byte), initial free space: 6,46 GB (6.462.078.976 Byte), urgency: 3
2019-01-29 17:51:17.368247+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Starting age based thinning of Time Machine local snapshots on disk '/'
2019-01-29 17:51:17.369425+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Skipping age based thinning of Time Machine reference snapshot 'com.apple.TimeMachine.2019-01-28-001417' on disk '/'
2019-01-29 17:51:17.370016+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Space based purging skipped Time Machine dataless reference snapshot 'com.apple.TimeMachine.2019-01-28-001417' on disk '/'
2019-01-29 17:51:17.571228+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Received unmount notification of stable snapshot
2019-01-29 17:51:17.592214+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Copied 2764 items (48 KB) from volume Macintosh HD. Linked 21952.
2019-01-29 17:51:17.831507+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Unmounted local snapshot: com.apple.TimeMachine.2019-01-29-174342 at path: /Volumes/com.apple.TimeMachine.localsnapshots/Backups.backupdb/MacBook Air (4)/2019-01-29-174342/Macintosh HD source: Macintosh HD
2019-01-29 17:51:17.987517+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Unmounted local snapshot: com.apple.TimeMachine.2019-01-28-001417 at path: /Volumes/com.apple.TimeMachine.localsnapshots/Backups.backupdb/MacBook Air (4)/2019-01-28-001417/Macintosh HD source: Macintosh HD
2019-01-29 17:51:18.194718+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Backup canceled.
2019-01-29 17:51:29.247123+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Unmounted '/Volumes/Time Machine-Backups' (disk2s2)
2019-01-29 17:51:30.857160+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Ejected disk2 from '/Volumes/com.apple.TimeMachine.Time Capsule-5E757F80-34D5-43A7-B4CB-7D2D9078DF8A/MacBook Air (4).sparsebundle'
2019-01-29 17:51:31.580731+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogInfo] Unmounted '/Volumes/com.apple.TimeMachine.Time Capsule-5E757F80-34D5-43A7-B4CB-7D2D9078DF8A'
2019-01-29 17:51:31.581571+0100  localhost backupd[38644]: (TimeMachine) [com.apple.TimeMachine:TMLogError] Failed to remove directory '(null)', error: 14 Bad address