Big Sur, Big Problems with Time Capsule

Not necessarily a solution, but not much else to try at this point. If the Time Capsule is 5+ years old, I would retire it.

Not sure if LaPastenague already mentioned this, but Time Machine backs up to an external drive connected directly to a Mac differently than it does to a network drive like a Time Capsule.

Time Machine backs up to a normal folder on an external drive connected directly to a Mac but backs up to a special container called a sparsebundle.......(now called a backupbundle in Catalina and Big Sur)......which is a more complicated way to back up. More chances for errors to occur.

Otherwise though, now that that TC is formatted vis APFS, the time machine backups ARE working.

The Time Capsule disk.....named "Data", unless you have changed the name of the drive.......is formatted in Mac OS Extended (Journaled). You cannot change this.

If you have "updated" to Big Sur and erased the Time Capsule hard drive, then the format of "Data" remains the same in Mac OS Extended (Journaled). But, the disk image......called a "backupbundle" that contains all the backups of the Mac running Big Sur is formatted in APFS.

So, the format of the Time Capsule disk remains the same, but the backup file is formatted in APFS on the Mac OS Extended (Journaled) drive. Gosh, I wonder what could possibly go wrong with this type of goofy setup.

When you run the backup of your Mohave Mac, the file that stores all the backups might be called a "sparsebundle" file. That disk image will be formatted in Mac OS Extended (Journaled) because Mohave cannot back up to an APFS disk image.

So, the Time Capsule hard drive can store backups of Macs that are running Big Sur and other operating systems as well.

The Mohave Mac will not be able to access the backups made by your Big Sur Mac using Time Machine. But, you could use Migration Assistant on the Big Sur Mac to move data from a backup of the Mojave Mac over to the Big Sur Mac. Complicated? Yes.

I had problems with Time Machine too after upgrading to Big Sur. These problems were completely solved by using a newly formatted drive (or deleting an old drive if you have more than one backup).

For Big Sur, Apple recommends using an APFS (or APFS encrypted) disk for your ™ backup, so in disk utility erase the entire disk and make an APFS partition on it. Direct Time Machine to that drive for a new backup (in addition to any other one or by replacing it as preferred by you). The first time it will take long if you have much data.

See https://support.apple.com/guide/mac-help/types-of-disks-you-can-use-with-time-machine-mh15139/11.0/mac/11.0

Good luck!

I’ve had a long session with Apple during which time we restarted everything to no avail, a PR start, pinged the ram, restarted in safe mode which actually instigated a back up of over 300 Gb which to around 7 hours over the network, but failed to make any further backups. Picking up the courage to continue where we left off, but I’m tending to think that previous comments have it in that there’s no solution until Apple address it.

I upgraded the second MacBook Pro (MBP) to Big Sur, which this MBP and an iMac Retina running Mojave are both connected to the same 3Tb Time Capsule (TC). That is all I did - nothing more - I did not erase the Data drive on the TC. It has been two days and so far, both computers are backing up without apparent issue to the same TC, so I am reluctant to do any more - to erase the Data drive on TC using Airport Utility and start over I mean.

Not sure why this MBP upon upgrade to Big Sur is having no apparent issues, while the first MBP upon upgrading to Big Sur looks like I had to erase the TC to which it was connected just to get it to start backing up properly.

I still DO notice that when the MBP running Big Sur is in the Preparing Backup stage the green light symbol turns off briefly in Airport Utility but this doesn't seem to affect internet connectivity / router functionality as far as WiFi.

One thing though is that I cannot seem to access the settings of this TC via Airport Utility, whether it asks for the PW or not, it never gets past the spinning circle while it is supposedly "Reading Settings" and then eventually just says that the device was not found and pops an orange triangle by it. Then I quit and reopen Airport Utility and the TC appears again just fine with the green light.

today (5 April) I have downloaded and done a fresh install of Sophos and it seems to be backing up. Don't know if they have fixed it (they said April 2021 for a fix) or if it's luck but so far, seems to be working.

Snapshots are created on your Mac's hard drive......not the Time Capsule. You have run Disk Utility / First Aid on your Mac's hard drive, correct?

I would suffer the long phone wait and pay the $95 or whatever the going rate is for Apple Support these days.

At this point, I think you are likely going to have to reinstall the operating system again. Unfortunately, there are no guarantees that this will work.

Not sure if Apple even supports the Time Capsule these days.

Good luck!

I also wiped the disc, My wifes air with Big Sur (and Sophos) could backup my MBP not...

Both to the same TC as well.

I had bought a NAS (WD MyCloud), spent hours with no succes so I am very happy it works again.

I think the technical term is it’s f€$ked. Exactly the same boat. Will have to wait and see if apple fix it. Works fine if you plug a hard disk direct to your machine. Just not over the network.

I’ve carried out the power off bit, fortunately I’d only recently (October) reconnected the capsule after household redesign etc, and had cleared it, so no extensive history to speak of. I’ll give it a try and go from there. The change in destination name is probably why Time Machine gives the ‘Time capsule is already in use’ message.

Interesting issues revealed by this thread.

I have a Time Capsule that currently serves as a way to backup 4 computers, and has worked pretty much flawlessly for quite some time.

One of these is a 2017 13 inch MacBook Air, which has plenty of free space on the internal drive, and has been backing up with no issues since put into service.

Until I upgraded it to Big Sur - now it gives me this error when it cannot complete a backup -

"Time Machine could not back up the disk “%@” because a snapshot of the disk could not be created."

All other computers continue to back up as before with no issues -

Any thoughts?