DSM 4's Timed Backup is terrific. I use it to keep the last 30 days versions of all files, stored on a different volume in the NAS.
However, I'm unable to copy or otherwise archive/backup this time machine like thing, say, to an external drive. The reason, I think, is as follows.
The Time Machine-like timed backup runs once a day by my schedule. On each run, a new folder tree is created. Files that haven't changed don't get copied of course, but a hard link (linux term) is put in the current backup, pointing to the youngest real file.
This is fine and good. But the DSM copy and backup utilities can't work because the first thing they do is sum up the required destination storage. In doing so, they sum in the size of the linked files. Example: if there are 30 days of timed backups and file A was unchanged all 29 days, there are 29 links to the original file. The DSM utilities estimate based on 29 times more storage than actually needed (ignoring the size of the links themselves). So the copy fails (not enough room in the destination). Even the folder status utility falters: it too sums the sizes wrong. After a very long delay, it displays the too large number.
I asked about this on the Syno forum but the answer was yes, DSM cannot do this backup of the timed backup. Maybe some linux dd shell command could do it. Though I know how to use a Linux shell, I'd like the automation tools to handle this without grunging around in chron/shell.
Anyone know of a way?
Yes, this is arguably anal... backing up a timed backup. But if that timed backup folder set is lost, so too is the history.
However, I'm unable to copy or otherwise archive/backup this time machine like thing, say, to an external drive. The reason, I think, is as follows.
The Time Machine-like timed backup runs once a day by my schedule. On each run, a new folder tree is created. Files that haven't changed don't get copied of course, but a hard link (linux term) is put in the current backup, pointing to the youngest real file.
This is fine and good. But the DSM copy and backup utilities can't work because the first thing they do is sum up the required destination storage. In doing so, they sum in the size of the linked files. Example: if there are 30 days of timed backups and file A was unchanged all 29 days, there are 29 links to the original file. The DSM utilities estimate based on 29 times more storage than actually needed (ignoring the size of the links themselves). So the copy fails (not enough room in the destination). Even the folder status utility falters: it too sums the sizes wrong. After a very long delay, it displays the too large number.
I asked about this on the Syno forum but the answer was yes, DSM cannot do this backup of the timed backup. Maybe some linux dd shell command could do it. Though I know how to use a Linux shell, I'd like the automation tools to handle this without grunging around in chron/shell.
Anyone know of a way?
Yes, this is arguably anal... backing up a timed backup. But if that timed backup folder set is lost, so too is the history.
