I have been running Time Machine on an network SMB mounted partition for a couple of weeks (using the trick where you disabled the time machine disk check
defaults write com.apple.systempreferences TMShowUnsupportedNetworkVolumes 1)...
I know it was a bad idea... but I have plenty of SMB space available at my lab, while no real hard disk (until today 😉 )
Everything went fine until today, where finally the disk filled up... and I got this in the console
20/11/07 15:10:42 /System/Library/CoreServices/backupd[11539] Trusting backup times for remote backups.
20/11/07 15:10:51 /System/Library/CoreServices/backupd[11539] Starting pre-backup thinning: 5.03 GB requested (including padding), 3.07 GB available
20/11/07 15:11:30 /System/Library/CoreServices/backupd[11539] Deleted backup /Volumes/Backup of Zig/Backups.backupdb/Zig/2007-11-19-145728: 3.07 GB now available
20/11/07 15:11:30 /System/Library/CoreServices/backupd[11539] Removed all 1 expired backups, more space is needed - deleting oldest backups to make room
20/11/07 15:12:20 /System/Library/CoreServices/backupd[11539] Deleted backup /Volumes/Backup of Zig/Backups.backupdb/Zig/2007-11-09-145354: 3.07 GB now available
20/11/07 15:13:08 /System/Library/CoreServices/backupd[11539] Deleted backup /Volumes/Backup of Zig/Backups.backupdb/Zig/2007-11-12-085647: 3.07 GB now available
20/11/07 15:14:02 /System/Library/CoreServices/backupd[11539] Deleted backup /Volumes/Backup of Zig/Backups.backupdb/Zig/2007-11-13-105151: 3.07 GB now available
20/11/07 15:14:57 /System/Library/CoreServices/backupd[11539] Deleted backup /Volumes/Backup of Zig/Backups.backupdb/Zig/2007-11-14-094201: 3.07 GB now available
20/11/07 15:15:49 /System/Library/CoreServices/backupd[11539] Deleted backup /Volumes/Backup of Zig/Backups.backupdb/Zig/2007-11-15-093340: 3.07 GB now available
20/11/07 15:16:58 /System/Library/CoreServices/backupd[11539] Deleted backup /Volumes/Backup of Zig/Backups.backupdb/Zig/2007-11-16-091426: 3.07 GB now available
20/11/07 15:19:39 /System/Library/CoreServices/backupd[11539] Deleted backup /Volumes/Backup of Zig/Backups.backupdb/Zig/2007-11-19-084944: 3.07 GB now available
20/11/07 15:19:51 /System/Library/CoreServices/backupd[11539] Deleted backup /Volumes/Backup of Zig/Backups.backupdb/Zig/2007-11-19-160038: 3.07 GB now available
20/11/07 15:20:25 /System/Library/CoreServices/backupd[11539] Deleted backup /Volumes/Backup of Zig/Backups.backupdb/Zig/2007-11-19-164736: 3.07 GB now available
20/11/07 15:21:14 /System/Library/CoreServices/backupd[11539] Deleted backup /Volumes/Backup of Zig/Backups.backupdb/Zig/2007-11-19-174849: 3.07 GB now available
20/11/07 15:21:39 /System/Library/CoreServices/backupd[11539] Deleted backup /Volumes/Backup of Zig/Backups.backupdb/Zig/2007-11-20-100005: 3.07 GB now available
20/11/07 15:22:07 /System/Library/CoreServices/backupd[11539] Deleted backup /Volumes/Backup of Zig/Backups.backupdb/Zig/2007-11-20-104417: 3.07 GB now available
20/11/07 15:22:39 /System/Library/CoreServices/backupd[11539] Deleted backup /Volumes/Backup of Zig/Backups.backupdb/Zig/2007-11-20-114450: 3.07 GB now available
20/11/07 15:23:00 /System/Library/CoreServices/backupd[11539] Deleted backup /Volumes/Backup of Zig/Backups.backupdb/Zig/2007-11-20-124449: 3.07 GB now available
20/11/07 15:23:00 /System/Library/CoreServices/backupd[11539] Error: backup disk is full - all 15 possible backups were removed, but space is still needed.
20/11/07 15:23:00 /System/Library/CoreServices/backupd[11539] Backup Failed: unable to free 5.03 GB needed space
20/11/07 15:23:01 /System/Library/CoreServices/backupd[11539] Backup failed with error: Not enough available disk space on the target volume.
20/11/07 15:23:03 /System/Library/CoreServices/backupd[11539] Ejected Time Machine disk image.
20/11/07 15:23:03 /System/Library/CoreServices/backupd[11539] Ejected Time Machine network volume.
Do you see where I am coming? this is already scary... it deleted ALL but one backups, without recovering one byte... Jez... without a warning (despite the check box in the TM pref option pane)
Look at this:
[zig:~] felix% mount
/dev/disk0s2 on / (hfs, local, journaled)
devfs on /dev (devfs, local)
fdesc on /dev (fdesc, union)
map -hosts on /net (autofs, automounted)
map auto_home on /home (autofs, automounted)
//felix@basso-cambo.laas.fr/local/users/felix on /Volumes/felix (smbfs, nodev, nosuid, mounted by felix)
This is the SMB partition:
[zig:~] felix% df -g /Volumes/felix/
Filesystem 1G-blocks Used Available Capacity Mounted on
//felix@basso-cambo.laas.fr/local/users/felix 66 63 3 96% /Volumes/felix
[zig:~] felix% ls /Volumes/felix/
Zig_0017f2c89d46.sparsebundle/
[zig:~] felix%
<here I mounted the sparsebundle image using the finder>
[zig:~] felix% mount
/dev/disk0s2 on / (hfs, local, journaled)
devfs on /dev (devfs, local)
fdesc on /dev (fdesc, union)
map -hosts on /net (autofs, automounted)
map auto_home on /home (autofs, automounted)
//felix@basso-cambo.laas.fr/local/users/felix on /Volumes/felix (smbfs, nodev, nosuid, mounted by felix)
/dev/disk2s2 on /Volumes/Backup of Zig (hfs, local, nodev, nosuid, journaled, mounted by felix)
[zig:~] felix% df -g /Volumes/Backup\ of\ Zig/
Filesystem 1G-blocks Used Available Capacity Mounted on
/dev/disk2s2 132 129 3 98% /Volumes/Backup of Zig
So the Backup partition pretend to use 129 Gig (weird as its containing SMB partition is 66 Gig big) and 3 Gig left...
[zig:~] felix% cd /Volumes/Backup\ of\ Zig/
[zig:/Volumes/Backup of Zig] felix% ls
Backups.backupdb/
[zig:/Volumes/Backup of Zig] felix% ls Backups.backupdb/
Zig/
[zig:/Volumes/Backup of Zig] felix% ls Backups.backupdb/Zig/
2007-11-20-141210/ 2007-11-20-151041.inProgress/ Latest@
[zig:/Volumes/Backup of Zig] felix% sudo ** -sk .
Password:
35637816 .
But all the files on this partition amount to 35 gigs... (which is indead more or less the size of one backup)... where are the other 31 gig gone? My explanation is that the space has not been properly recovered after the old backups deletion... (which indeed also explains why backupd deleted ALL but one backups)
In any case, I would advise any SMB mounted partition Time Machine user to NOT rely completely on those backup. I will try to see if one can recover the space in a sparsebundle image... but even so, it makes the whole process dangerous.
You have been warned...
Moreover:
[zig:/Volumes/felix] felix% hdiutil compact Zig_0017f2c89d46.sparsebundle
Starting to compactâ¦
Reclaiming free spaceâ¦
................................................................................ ....................................................................
Finishing compactionâ¦
Reclaimed 19.5 GB out of 97.9 GB possible.
[zig:/Volumes/felix] felix% df -g .
Filesystem 1G-blocks Used Available Capacity Mounted on
//felix@basso-cambo.laas.fr/local/users/felix 66 43 22 66% /Volumes/felix
[zig:/Volumes/felix] felix%
Note that I only recover (by hand) 22 gig while 31 should be available... but this is explained in man hdiutil:
"For SPARSEBUNDLE images, completely unused band files are simply removed."
Completely... so Iguess only 22 gig of bands were free 9 gigas are in band which are partially used by good data.
[zig:/Volumes/felix] felix% cd /Volumes/Backup\ of\ Zig/
[zig:/Volumes/Backup of Zig] felix% df -g .
Filesystem 1G-blocks Used Available Capacity Mounted on
/dev/disk2s2 132 109 22 83% /Volumes/Backup of Zig
[zig:/Volumes/Backup of Zig] felix%
So the space has been indeed returned to the SMB volume... and I was able to restart TM after that and complete a backup...
In any case, I say it again... do not rely on SMB mounted partition based TM backup.
As for me, I am ordering a 200 gig external HD :-D