PowerMac TimeMachine Server

[hadit]

Hi all,

Just wondered if anyone could help me. About 6 months ago we dug an old PowerMac G5 out and started using it as a TimeMachine Backup Server. Basically it has a 2TB drive in there shared on the network and we have 9 Mac (7 imacs & 3 Macbook) backup up to it, with encryption.

However, we have 2 new starters, so we require additional devices, which will bring the 10 concurrent users limit in to effect. Two main questions, as i'd like to keep the G5 running.

1. If 10 Clients are backing up, will the additional TimeMachines (on the clients) just cue up? Or will the additional clients just refuse to connect then show a error and not try again?

2. Would it be worth getting hold of a copy of OS X 10.5 Server Unlimited Clients? Thus making restoring easier as I'd currently have mount the network drive via terminal to restore a Client. However I'm assuming with OS X Server I wouldn't have to do this? Am I correct?

Any suggestions would be greatly appreciated.

Thanks

Andy

 

[eyoungren]

Hmmm…can you explain this limit and what is imposing it?

I'm wondering because I have a USB dock attached to my Quad with a 1TB drive in it and my Quad handles backups from two laptops (anywhere they happen to be) and one off-site G5 as well as it's own backup.

I'm not aware of any limit other than the physical capacity of the hard drive. Other than the Quad, the rest of the backups are to individual sparse disk images as that is the nature of networked backups. Or at least it is in the way I have it set up I guess.

 

[NathanJHill]

Yes, this is baked into Leopard (and maybe subsequent OS versions too). A server version would let you go past this. (see the attached screenshot)

I think the error message other users will get will be something annoying like - Can't connect to server. Please try again later. Not super helpful.

My question is whether other software gets around that limit, like if you compiled and ran a separate FTP app instead of the one coming with your Mac. Is it just built-in software and underlying OS things - like file sharing, afp, etc? Or is the limit on 10 users deeper than that even?

 

[hadit]

Hmmm…can you explain this limit and what is imposing it?

I'm wondering because I have a USB dock attached to my Quad with a 1TB drive in it and my Quad handles backups from two laptops (anywhere they happen to be) and one off-site G5 as well as it's own backup.

I'm not aware of any limit other than the physical capacity of the hard drive. Other than the Quad, the rest of the backups are to individual sparse disk images as that is the nature of networked backups. Or at least it is in the way I have it set up I guess.

Hi eyoungren,

No, there is no physical limit to how much space there is on the drives. However there is a limit on how many clients can connect to OS X 10.5 at once. This is the problem I'm going to face.

Yes, this is baked into Leopard (and maybe subsequent OS versions too). A server version would let you go past this. (see the attached screenshot)

I think the error message other users will get will be something annoying like - Can't connect to server. Please try again later. Not super helpful.

My question is whether other software gets around that limit, like if you compiled and ran a separate FTP app instead of the one coming with your Mac. Is it just built-in software and underlying OS things - like file sharing, afp, etc? Or is the limit on 10 users deeper than that even?

Hi NathanJHill,

I'm sure a long, long time ago (back when OS X 10.5 was current), there was a way of removing the limit. As it simply much be a piece of code somewhere as I can't believe Apple reengineered their Server OS between MB005Z/A and MB004Z/A.

Anyone any ideas?

Thanks

Andy

 

[eyoungren]

Hi eyoungren,

No, there is no physical limit to how much space there is on the drives. However there is a limit on how many clients can connect to OS X 10.5 at once. This is the problem I'm going to face.

I get that now.

I'm curious though…is everyone's TM backups timed so accurately that you'd have ten people at once connecting and backing up or is it a matter of these computers are ALWAYS connected.

I ask because the way it works for me is a little different.

When a TM backup goes off on one of my machines it connects, does the backup and then disconnects. Sometimes things overlap and I may get more than one connection, but when done the Mac backing up always disconnects.

Is this not going to be the case in your situation?

 

[hadit]

I get that now.

I'm curious though…is everyone's TM backups timed so accurately that you'd have ten people at once connecting and backing up or is it a matter of these computers are ALWAYS connected.

I ask because the way it works for me is a little different.

When a TM backup goes off on one of my machines it connects, does the backup and then disconnects. Sometimes things overlap and I may get more than one connection, but when done the Mac backing up always disconnects.

Is this not going to be the case in your situation?

Technically no/yes. Even if you set every client to backup together in one go. I can't see them keeping that that timing etc. Heavily used devices will backup more frequently and less used devices may be switched off for a day and turn on mid afternoon. I suspect you would probably be ok up to 15-20 devices before you noticed a problem.

My main concern more was that if computer 11 decides to try and back up and 1 - 10 are already backing up. Is it intelligent enough to try again, or will it simply throw the error, then never try and backup to that disk/drive/media again until told to?

Also I'm thinking maybe OS X 10.5 Server Unlimited Client might be a safer option as for restoring whole clients, the server will automatically be seen from the restore sector. Saves the effort of mount the network drive as a volume in terminal.

I'm mainly just interested in if anyone else had a similar experience.

Thanks

Andy

 

[eyoungren]

My main concern more was that if computer 11 decides to try and back up and 1 - 10 are already backing up. Is it intelligent enough to try again, or will it simply throw the error, then never try and backup to that disk/drive/media again until told to?

Well…I can relate my experience. Don't know if that will be helpful or not.

Generally, with my networked backups if the drive is not available I get an exclamation mark on my TM icon. If I click on that it says "Backup delayed". It will then attempt to execute upon it's next scheduled backup.

Lather, rinse, repeat until it successfully completes a backup.

I suspect that would probably be what you encounter because if a connection is refused the drive does not mount and is thus not available. So, the backup would simply be delayed.

 

[hadit]

Well…I can relate my experience. Don't know if that will be helpful or not.

Generally, with my networked backups if the drive is not available I get an exclamation mark on my TM icon. If I click on that it says "Backup delayed". It will then attempt to execute upon it's next scheduled backup.

Lather, rinse, repeat until it successfully completes a backup.

I suspect that would probably be what you encounter because if a connection is refused the drive does not mount and is thus not available. So, the backup would simply be delayed.

Excellent, thanks for that it's very encouraging. I'd rather not spend the £399 on a Server DVD.

Amazing a 14 year old bit of kit, is at the heart of a 21st century network, providing a faultless service to 2 other Servers and 10 clients.

Did you know what the maximum hard drive size these can take?

Thanks for all your help.

 

[eyoungren]

Did you know what the maximum hard drive size these can take?

Thanks for all your help.

I'm not sure. However, I can tell you that my secondary drive on my Quad G5 is 4TB. It's a SATA 3 drive so I had to jumper it but the Mac has no issue seeing all 4TBs.

I suspect it would handle a 6 or 8 TB HD just fine.

 

[bunnspecial]

Did you know what the maximum hard drive size these can take?

If you want the drive to be bootable, 2tb is the limit for APM drives. I've never tried, but I think other folks have had issues trying to partition larger drives.

G5s have zero issues reading MBR and GUID drives. I strongly recommend the latter. I know you can go over 2tb with GUID and you also get the other benefits like GUID. You just can't boot an Intel Mac off it.

 

[eyoungren]

Yeah, I probably should have mentioned that my secondary drive is GUID partitioned.

 

[hadit]

If you want the drive to be bootable, 2tb is the limit for APM drives. I've never tried, but I think other folks have had issues trying to partition larger drives.

G5s have zero issues reading MBR and GUID drives. I strongly recommend the latter. I know you can go over 2tb with GUID and you also get the other benefits like GUID. You just can't boot an Intel Mac off it.

Yeah, I probably should have mentioned that my secondary drive is GUID partitioned.

Thanks of the info. Yes I have a 250Gb boot drive, then a 2Tb GUID drive shared. Or should I say I did. I took the plunge and had a spare hour today, so I decided to reformat and install OS X 10.5 Server. Expecting it all to work wonderfully... Oh how I was wrong.

I enabled TM in Server Preferences, the clients (10.11/10.12) see it on TM preferences straight away, however when I try and connect I get "The selected network backup disk does not support the required capabilities". I also tried turning TM Server off and just user a share like before. However the Clients are refusing to see the drive in TM preferences.

Any ideas? If not I'll just restore from backup and go back to the old way.

 

[eyoungren]

In terminal on each client:

defaults write com.apple.systempreferences TMShowUnsupportedNetworkVolumes 1

 

[hadit]

In terminal on each client:

defaults write com.apple.systempreferences TMShowUnsupportedNetworkVolumes 1

Thanks, tried both ways. Unfortunately it's still not showing. Any other ideas?

 

[eyoungren]

No, I'm sorry. I'm only familiar with the client aspects of OS X. No experience with Server.