So far I've found this info on the apple support sites:
https://support.apple.com/en-us/HT202784#nas
Which says - No problem using TM with NAS on Big Sur as long as you set it up under SMB and recommends that I look at the manufacturers claims.
That's not exactly what it says, and you need to make sure the NAS claims that it supports the "Time Machine over SMB" specification. There are a set of network functions which its file server must support in order for it to work correctly. Does it? I don't know. I can't get anybody who is having NAS Time Machine issues to state that the manufacturer has that statement in its documentation. It is not sufficient for the NAS manufacture to claim it supports Time Machine or has a Time Machine server, or any other words to that effect which do not include "Time Machine over SMB" specification.
But some older threads (about El Capitan) I've seen from clever people like Linc Davis (https://discussions.apple.com/thread/7356107) - say 'yes TM will back up over NAS, but you won't be able to "restore" from the back up despite what the manufacturers claim'. Which seems to be a major problem. Is that still the case?
That is because up until Apple switched over to SMB networking protocol, they used Apple Filing Protocol (AFP). Apple never licensed AFP to anyone, so the NAS manufacturers used a reverse engineered hack of AFP called Netatalk. Since they couldn't figure out what extra information Time Machine was using over AFP, there were often problems, primarily the inability to actually restore. The support for Time Machine over SMB to a NAS started around 2016. From what I've found, the NAS software needs to be running Samba 4.8 or later.
Is there a definitive source out there which i can rely upon when choosing a system to buy? If not, does any one have any recommendations?
This forum is replete with problems using a NAS for Time Machine. Not so much for using an external drive. A lot of that stems from trying to use it over AFP which was never supported by Apple.
which acts both as a RAID backup and as a media server
I would never use a device for a dual purpose like that. If it dies, you lose it all and you have to spend a large sum to replace it all. Maybe if you set it up RAID 10 you can replace drives as they wear out, but you're going to have to spend a lot to get 12TB usable with RAID 10.
When Apple started marketing the Time Capsule, I thought that was one of their stupidest ideas. Half of it is going to break, wear out, or become obsolete before the other half.
A reliable backup plan has more than one backup, and one of those backups should be stored off-site. No way to take your NAS off-site if you are using it for a media server.
If you have an iMac, plug in an external drive or three and you can back up the iMac and any other notebook Macs can back up wirelessly.
I've got several external drives connected to my Mini. It has its own dedicated Time Machine drives and I have drives for the notebooks. My Time Machine maintenance steps are:
- Turn it On
- Forget about it.
