Time Machine just went to do a back up and bounced up the message:
Time Machine completed a verification of your backups on “WDMyCloudMirror.local”. To improve reliability, Time Machine must create a new backup for you.
Click Start New Backup to create a new backup. This will remove your existing backup history. This could take several hours.
Click Back Up Later to be reminded tomorrow. Time Machine won’t perform backups during this time.
I gather that “To improve reliability…” is code for “your backup is completely stuffed”…
TimeMachine is (was) backing up a MacBook Pro to a NAS of which 1TB had been allocated to TM and still had about 490GB free. (So it’s not an out of space issue, and if it was doesn’t it remove earlier version and keep a ‘rolling backup’?).
The entire NAS is backed up periodically to a couple of external USB disks so I do have older copies of the Time Machine files.
Does anyone know how TM keeps track of where it’s up to? Is the “index” / control config stored on the the Mac or within the sparse bundle? My thought was, can I copy the older backup off the USB onto the NAS and set it going again (thus retaining my TM history) or will that result in a mismatch between the backup files & where TM thinks it’s up to, thereby completely confusing it?
Thanks, I might give it a whirl though it’s going to have to wait till the weekend, hopefully there’s no way I can make it any worse than it already is! And I’m definitely not brave enough to start tampering with the innards!
If you can afford do do so, pick up a new drive for your new TM backup. Put the old one in a drawer and, once you are confident with the new TM backup use the old drive (suitably reformatted and checked for bad sectors) as a carbon copy clone (or similar mirroring software).
Of course, if you have already done the above, you would have an older drive you could use this time
@GraemeS, Thank you for that link, I’d not initially twigged on to that probably being related as it had been ticking away quite happily for some time (I’d figured if that was it then it’d have gone boom sooner). Having reading that thread a bit more attentively it seems like a strong candidate. A re-install is as about as appealing as toothache though
thanks @Philrob, funnily enough I’d already been toying with the idea of getting another drive & kicking off a 2nd / separate Time Machine backup before this one blew up. Might be a good time to dive in on that.
@SpivR, thanks, I think after this I’ll be completely re-working how I do backups. I had been very pleased with TM given (as you point out) the set-it-and-forget-it nature, flaky is just not a feature you really want in a back-up tool though.
Bomb-proof… Bomb-proof is what we’re all looking for in a backup tool.