Current status of mac time machine support?

[drumstyx]

Doing all kinds of reading here, but a lot of threads are relatively old, and very few deal with High Sierra.

 

I understand it used to be required that TM backups had to be on a single disk share, rather than a user share, is this still true? That'd be a damn shame, since I'd love to just not think about it, and I really don't understand how it could be a problem since the disks backing up shares are supposed to be invisible to the clients.

Backup over AFP still works? There was some talk about SMB-only backup to APFS systems, but since unraid isn't APFS, I assume a non-issue? I've noticed that when I connect to AFB vs SMB on my macbook though, AFP is *much* slower at browsing...hope this doesn't translate to TM performance...

 

Any advice would be appreciated!

[kizer]

I know it doesn't answer your question the way you wold like to do it. However this is how I do it with my Laptop and my Desktop.

 

Purchased a 3TB drive and I split it into 2 partitions. 2TB and 1TB since my laptop is a lot smaller than my desktop.

I backup my desktop on the first partition named Desktop

I backup my Laptop on the second partition named Laptop

I place the drive on a shelf in my closet for safe keeping. 

 

I know its not a super simple over the network option, but Its always worked for me and honestly I find it so simple that I didn't even bother pursuing it in unRAID anymore

[drumstyx]

If I have to go as far as to have a completely separate disk to back up my macs, I'd rather just throw it in the unraid box and use a single disk share for it. Even better would be, like I mentioned, user share backup, but at the very least I want things in one place.

 

All part of my plan to server-ify my life  I don't have any spinning drives anywhere but my server now. Heck, I imagine someday this won't be an issue because I'll do my computing ON my server via a dumb client, but it's not quite there yet.

[Delarius]

I can't speak to High Sierra TimeMachine but it's been working perfectly with no configuration issues or performance concerns using El Capitan. Hopefully sometime I'll be able to upgrade to the newer OS but it just doesn't seem necessary as my 2008 Macbook is more than fast enough to run everything I need.

 

I'm running the latest unRaid and OSX 10.11 (El Capitan)

When I set this up last year, I simply selected the time machine 'share' in UnRAID when setting it up, then pointed Time Machine at the afp share.

It's been working flawlessly for almost a year now. Tested that it was working last week and appears to be working fine.

 

[kizer]

2 hours ago, drumstyx said:

If I have to go as far as to have a completely separate disk to back up my macs, I'd rather just throw it in the unraid box and use a single disk share for it. Even better would be, like I mentioned, user share backup, but at the very least I want things in one place.

 

All part of my plan to server-ify my life  I don't have any spinning drives anywhere but my server now. Heck, I imagine someday this won't be an issue because I'll do my computing ON my server via a dumb client, but it's not quite there yet.

 

Totally understand. 

 

I just know 3 or 4 OS's ago I have nothing but corruption problems with my Time Machine Backups and I've had zero issues doing it my way. However I might have to try it again since @Delarius seems to have it working. 

[drumstyx]

3 hours ago, Delarius said:

I can't speak to High Sierra TimeMachine but it's been working perfectly with no configuration issues or performance concerns using El Capitan. Hopefully sometime I'll be able to upgrade to the newer OS but it just doesn't seem necessary as my 2008 Macbook is more than fast enough to run everything I need.

 

I'm running the latest unRaid and OSX 10.11 (El Capitan)

When I set this up last year, I simply selected the time machine 'share' in UnRAID when setting it up, then pointed Time Machine at the afp share.

It's been working flawlessly for almost a year now. Tested that it was working last week and appears to be working fine.

 

 

Is it a regular share along with all your other data, or is it a share created specifically for this on separate disk(s?)?

[Delarius]

It's just a standard share, shows under /mnt/user/Timemachine as well as /mnt/disk1/Timemachine

I read through the forums thinking this might be challenging but it worked with few issues from the first day (apart from an issue with a wireless bridge.) Seems like I might have been lucky as this doesn't seem to work for everyone. Of course, the scope of my usage is very limited - my entire Mac disk usage is 70GB but on the other hand, I'm only able to run at 100megabit network speeds and have crazy ping times on my LAN (35ms+ is typical.)

Every month or so I will get a 'failed to find backup disk' error but that seems related to an ambitious check just as I open the laptop lid and subsequently works fine.

[drumstyx]

My macs are small(ish) in hard drive, as they use the small 256gb SSDs. The edge-case issues I've heard of are when a backup spans multiple disks...I can't for the life of me understand why that would be (again, invisible to the client) but I've read some things, so of course I'm a little wary!

I'll give it a shot anyway...see what happens...

[drumstyx]

Does your share have other files on it as well, or is it wholly dedicated to timemachine?

[pwm]

10 hours ago, drumstyx said:

The edge-case issues I've heard of are when a backup spans multiple disks...I can't for the life of me understand why that would be (again, invisible to the client) but I've read some things, so of course I'm a little wary!

When writing files to a user share in unRAID, it's important that the disk reservation is large enough that the full file will fit. If the disk reservation is smaller than the largest file your backup writes, then the backup can fail.

[drumstyx]

3 hours ago, pwm said:

When writing files to a user share in unRAID, it's important that the disk reservation is large enough that the full file will fit. If the disk reservation is smaller than the largest file your backup writes, then the backup can fail.

 

So again with the multi-disk problems -- it's just a huge set of band files, not a single file, I don't know how it could possibly be affected, but oh well. Fortunately, my MBPs have small drives (because of course I have most of my large storage on my server), I broke down and switched the only 1TB drive I have (unused in there, of course) to a single-disk user share, to sidestep any potential issues.

What's the difference between a User share with 1 included disk and a disk share anyway?

[itimpi]

4 minutes ago, drumstyx said:

What's the difference between a User share with 1 included disk and a disk share anyway?

Well one big difference is that disk shares have fixed names whereas user shares have names specified by the user!     Another difference is that user shares can be configured to have properties as to whether a cache disk (if present) can be used as interim storage before mover gets involved.   A disk share could also have files belonging to several User shares unless you have taken specific action in your settings to stop this happening.

[pwm]

1 minute ago, drumstyx said:

So again with the multi-disk problems

Most situations don't give multi-disk problems.

 

If storing 50GB large BD ISO images, it's enough to reserve 50GB on each disk. And with normal disks being 4TB and larger, it isn't a very high percentage of the total disk space. 50GB would be 1.25% of a 4TB drive.

 

I very seldom use Mac machines so I haven't looked at how Timemachine stores data. But backup software that creates huge backup files can get into troubles when saving to a multi-disk target. But most backup software that creates backup archives has a max destination file size - often less than 4GB - and split the backup into as many destination files as needed. In that case, the backup software will not be able to notice that the unRAID user shares have the data splitted over multiple disks.

 

But once more - that requires that the disk reservation is larger than the band size used by the backup software so unRAID will shift to the next destination disk before the previous disk runs full.

[drumstyx]

Time Machine bands are absurdly small -- 8.something MB. I dunno, at least for now it's probably better than nothing, and it's on a disk I don't use. When that drive gets upgraded to a 4TB (when it fails) I'll look at changing things up I suppose.

[pwm]

4 minutes ago, drumstyx said:

Time Machine bands are absurdly small -- 8.something MB. I dunno, at least for now it's probably better than nothing, and it's on a disk I don't use. When that drive gets upgraded to a 4TB (when it fails) I'll look at changing things up I suppose.

Even tiny bands will fail for a multi-disk share if the drive has zero as reservation limit.

[Delarius]

Ahh,

Yes, I think I see how this could go wrong. Fortunately, while my 'backup' time machine share was initially allowed to span disks - I've set it to only use 1 disk. The main reason being I have two disks in the array - one is around 10 years old. I figured given how that disk is pretty much ready to fail it didn't make sense to put a backup on it.

I do however look forward to the day when it entirely fails and I can verify that the parity disk can actually rebuild the contents.

[JonathanM]

9 minutes ago, Delarius said:

The main reason being I have two disks in the array - one is around 10 years old. I figured given how that disk is pretty much ready to fail it didn't make sense to put a backup on it.

I do however look forward to the day when it entirely fails and I can verify that the parity disk can actually rebuild the contents.

Yes, but what happens when a different disk fails unexpectedly? Then you will probably lose the contents on both disks.

 

It's a very bad idea to leave bad disks in an array, you are pretty much staking the safety of your data on the bad disk, hoping that it dies first. I made that mistake many years ago, and lost a significant amount of data. Now I don't keep any questionable disks in the array, AND I keep backups elsewhere.

[Delarius]

It is a very bad idea to leave known failing disks in the array - I absolutely concur - IF you value your data in any way. However, given I've got multiple backups on new disks (and in the cloud) and am entirely happy to lose ALL the data anyways - it's not a risk. In fact, as stated I look forward and yearn for a (multiple) disk failure. As to why I have multiple backups and have no use for them - I keep rigorous backups as a proof of concept. If all my backups and drives failed suddenly - I'd be thrilled at the prospect of rebuilding, not concerned about loss of data.