Time Machine backups failing: "backup disk is not in Mac OS Extended (Journaled) Format"

[enfolder]

I have been using my Time Capsule for many years without incident. We backup two MacBooks to this Time Capsule using Time Machine. I recently upgraded my Macbook Pro to Catalina, which went fine, but a few days ago all backups began failing. I get the error message:

"The backup disk is not in Mac OS Extended (Journaled) format, which is required."

Nothing has changed about the backup disk, and the other MacBook continues to back up just fine.

A reboot of my MacBook Pro got it to successfully complete a backup, but then the error came back.

I found some threads that an app called "App Cleaner" can cause this error, but I have no such app.

Any troubleshooting suggestions?

 

[chscag]

Welcome to our forums.

Have both of your MacBooks been upgraded to Catalina or is it just the one that generates the error? If after a reboot it backed up okay, it's possible that it did not "see" the Time Capsule and tried to perform a backup anyway, thus the error.

An upgrade to Catalina also formats the hard drive or SSD to APFS which currently is not compatible with Time Machine.

 

[enfolder]

Welcome to our forums.

Have both of your MacBooks been upgraded to Catalina or is it just the one that generates the error?

One is still Mojave.

If after a reboot it backed up okay, it's possible that it did not "see" the Time Capsule and tried to perform a backup anyway, thus the error.

I don't follow. It sees the drive, it just says it's the wrong format.

An upgrade to Catalina also formats the hard drive or SSD to APFS which currently is not compatible with Time Machine.

I don't understand how this could be true. Not only have I successfully backed this MacBook Pro with Catalina up to Time Machine before, I've done a complete restore from it! That is not consistent with an upgrade to Catalina being incompatible with Time Machine.

 

[chscag]

You misunderstood what I wrote. Time Machine will back up a hard drive or SSD that is formatted to APFS, however, the drive that the data is being backed up to must be formatted as HFS+.

I don't follow. It sees the drive, it just says it's the wrong format.

Are you sure it "sees" your Time Capsule and not something else? It doesn't make any sense if it "sees" your TC and then tells you that it is in the wrong format. That's why I wrote above about a Catalina installation formatting the drive to APFS, not meaning that it formatted your TC to APFS.

Why is it then that your other MacBook Pro which is running Mojave backs up okay? What format is that machine using?

 

[IWT]

Just to emphasise, rather than intrude upon, what our Admin chscag said:

Irrespective of the Source Format: Mac OS X Extended (Journaled) aka HFS+ or APFS - or whether it has a SSD or spinning platter Drive; the Time Machine External Hard Drive must be formatted Mac OS X Extended (Journaled).

Maybe the Time Capsule is near full; or failing?

Ian

 

[enfolder]

Just to emphasise, rather than intrude upon, what our Admin chscag said:

Irrespective of the Source Format: Mac OS X Extended (Journaled) aka HFS+ or APFS - or whether it has a SSD or spinning platter Drive; the Time Machine External Hard Drive must be formatted Mac OS X Extended (Journaled).

Maybe the Time Capsule is near full; or failing?

Ian

The Time Capsule is at about half capacity. It could be failing—but only one MacBook Pro is having this problem.

I presume the Time Capsule drive is indeed in the correct format because I've been using it continuously for years on both machines.

 

[enfolder]

You misunderstood what I wrote. Time Machine will back up a hard drive or SSD that is formatted to APFS, however, the drive that the data is being backed up to must be formatted as HFS+.

No, I think I understood that you were referring to the format of the Time Machine drive, not my MacBook Pro. I've been using it continuously for years on both machines so I think it's in the correct format.

Are you sure it "sees" your Time Capsule and not something else?

Well, the Time Capsule shows up in my Finder, has the correct name, and I can see my backups as a sparsebundle. It also has the correct name in the Time Machine preferences pane. So, I think it sees it.

It doesn't make any sense if it "sees" your TC and then tells you that it is in the wrong format. That's why I wrote above about a Catalina installation formatting the drive to APFS, not meaning that it formatted your TC to APFS.

I agree it doesn't make sense, especially since the problem is intermittent! For instance, the last backup succeeded! As did the first one I tried after a reboot of my MacBook Pro.

Why is it then that your other MacBook Pro which is running Mojave backs up okay? What format is that machine using?

I'm not sure what format the Mojave laptop is in.

 

[ferrarr]

Have you reset your Time Capsule?

How to reset your AirPort base station - Apple Support

 

[enfolder]

Yes, did that last night and it seems like I've had some successful backups since then. Some have failed with the same error though.

It seems like the problem is intermittent and the workaround is to wait for a backup to work, and hope rebooting things gives you a good backup if it's been a while. *sigh*

 

[IWT]

@enfolder,

You said

I'm not sure what format the Mojave laptop is in.

Very easy to find out. Open Disk Utility (DU). This is found in Finder > Applications > Utilities > Disk Utility

After opening DU, look to the left where all Drives (Internal and attached) will be shown - as in the screenshot below. Click on Macintosh HD as per red arrow and look to your right where the Format will be shown in two places (red arrows again).



Ian

Edit: If by any chance you don't see the indents, then click on View (top left) and select Show all Drives; but I don't think you will need to do that.

 

[ferrarr]

Maybe there is a conflict if one Mac is trying to backup at when the other one already is? Is there a log from Time Capsule that shows this information, or maybe you can get that logs from both Macs Time Machine?