Time Machine backup fails with disk not Mac OS Extended

[Lt. Cmdr LeForge]

I'm using a DS718+ and I setup the Time Machine options. I have an Mac Mini w/ Apple M2, an iMac Retina, Late 2015 running Monterey and a VitrualBox VM installed as Mac Mini 2018 running Catalina. On the two real machines Time Machine backs up fine. But on the Catalina VM the backup fails with message that the backup disk is not in Mac OS Extended (Journaled) format. I've had other VM that I thought were able to use the DS718+ just fine. But I've recently reloaded the VM and now I get this error.

I've got the lastest NAS updates installed. I am also using the NAS as my Windows backup destination. The Mac articles say to reformat the disk to be OS Extended which, of course, is not an option. Should the DS718 be able to handle this backup method from this version of Mac OS?

Is there something on the NAS that I can do to get this to work. I am also researching this on the Mac OS side to see if there's something I need to do. It's possible I'm mistaken and using the TM with Catalina to the NAS never worked.

Thanks for any help.

This post includes affiliate links. As an Amazon Associate, SynoForum.com may earn a commission if you make a purchase — at no extra cost to you.
It helps support our community! Learn more...

 

[Rusty]

Welcome to the forum!

Catalina VM the backup fails with message that the backup disk is not in Mac OS Extended (Journaled) format

This is a macos alert and I would say 99% has nothing to do with the NAS side. If you are using a TM backup configured by that virtual Mac, than the error is coming from the OS side of things.

Or, are you backing up the whole VM as a file? If so how exactly?