After partitioning external drive network Time Machine instance can't back up

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After partitioning external drive network Time Machine instance can't back up

This is a re-post with additional background information requested by several responders:

I recently added a G-Speed Q RAID array to my MAC PRO to use exclusively for back-up with Time Machine. I purchased this RAID array from the Apple store, so assume that means it's acceptable to use for this purpose. Maybe that's a bad assumption on my part. In any event, it worked great with Time Machine on my MAC PRO. The G-speed array is connected to my Mac Pro via Firewire 800 port for now. I am awaiting delivery of an eSATA expansion card for the Mac Pro which I intend to switch to when it arrives. In any event, it is not configured or capable of acting as an NAS device. It is a shared external drive on the MAC PRO.

My next step was to share the external device over my hardwire gigabit LAN with my wife's iMAC so she could back-up with Time Machine as well. It also worked great. Both Macs are connected via hardwire gigabit, supported by an Actiontec Q1000Z router. The LAN performs flawlessly for all other purposes, including over 30 network devices connected via either hardwire or 802.11n. Both machines are running Lion 10.7.4. (not server)

I then started reading posts that suggested the two Time Machine instances would compete for space on the back-up array and eventually it would fill up and I'd have problems. The solution, everyone says, is to partition the external drive and assign one to each Time Machine back-up. It makes perfect sense to me. I did this following the step-by-step instructions (#22) from Pondini's site. Both partitions are formatted with MAC OS Extended (journaled). Everything seemed to be working great until the remote client tried to run back-up. The remote Time Machine instance fails with the "Disk does not support AFP featues" error message.

Current status is as follows, local time machine back-up works fine on its partition. Remote machine finds and connects to its assigned partition once I provide correct user name and password, but fails while Time Machine is "searching for backup device" with the AFP error message. The remote (sending) machine is connecting as a dedicated user and not as "Guest".

I can write test files directly to the remote back up partition from either mac and I can read, modify and save files directly to this partition from either mac.

Please let me know if any additional information related to configuration is needed. Any suggestions would be greatly appreciated.

Mac OS X (10.7.4)

Posted on May 30, 2012 12:14 PM

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Answer 1

Pondini

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May 30, 2012 12:58 PM in response to SMS5572

(Sorry about responding to the old thread; I didn't see this one, and didn't notice the date on it). 😟

SMS5572 wrote:

. . .

My next step was to share the external device over my hardwire gigabit LAN with my wife's iMAC so she could back-up with Time Machine as well. It also worked great.

Are you saying it backed-up to the same partition on the same drive you were using for your MacPro, but won't back up to the second partition? I didn't quite get that before.

That's quite odd. What partition map scheme is on the external? It seems unlikely, but if it's MBR (Master Boot Record), that might be the problem.

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Answer 2

SMS5572 Author

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May 30, 2012 12:59 PM in response to SMS5572

Just to clarify, one additional point.

Once the dedicated partition for the remote back is mounted, it shows up in the "Select Disk" drop-down list in Time Machine, just like all other network available drives. I can select it as the back-up target drive ok. The failrue doesn't happen until Time Machine begins a back-up cycle and tries to start backing up to this partition.

That's wehn the AFP error message comes up and the back=up fails.

Hope this helps.

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Answer 3

SMS5572 Author

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May 30, 2012 1:03 PM in response to Pondini

Yes, when I only had one partition on the external array, both Time Machine instances were able to back-up to that single partition. It was only after creating a second partition that the remote back-up failed.

That's the part that has me stumped.

I'm not certain what MBR is referring to. When I look at both partitions using Disk Utility, both show as Mac OS Extended (journaled) formats. Is there something else to look at?

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Answer 4

Pondini

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May 30, 2012 1:06 PM in response to SMS5572

SMS5572 wrote:

. . .

I'm not certain what MBR is referring to. When I look at both partitions using Disk Utility, both show as Mac OS Extended (journaled) formats. Is there something else to look at?

Click the top line for the drive in Disk Utility's sidebar.

The Partition Map Scheme should be shown at the lower right.

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Answer 5

SMS5572 Author

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May 30, 2012 1:10 PM in response to Pondini

Apple Partition Map

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Answer 6

Pondini

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May 30, 2012 1:20 PM in response to SMS5572

Rats. 😟

GUID (aka, GPT) is preferred (if you ever have to reformat), but APM should work fine as far as I know. (MBR is a Windoze setup, and sometimes if there are multiple partitions on such a drive, some aren't available to TM, for some reason).

From the Help:

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Answer 7

Pondini

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May 30, 2012 1:25 PM in response to SMS5572

Just to be sure, try it to the first partition temporarily. I can't imagine it will work, but it might be worth a shot.

(Time Machine won't back up the iMac to the MacPro's backups -- it will create a sparse bundle disk image for them, which you can just delete.)

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Answer 8

SMS5572 Author

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May 30, 2012 1:56 PM in response to Pondini

You are correct. I can mount the other partition on the remote machine and Time Machine finds it in the Select Disk window, but the same failure results.

I think that's a better outcome than if it had worked on this partition. That would have been really confusing.

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Answer 9

Pondini

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May 30, 2012 2:38 PM in response to SMS5572

Well, it would at least have narrowed the problem down, and perhaps have led to a workaround.

It's a long shot, but perhaps something is damaged in your installation of OSX. You might want to install the 10.7.4 "combo" update, per Installing the ''combo'' update and/or Reinstalling OSX.

If still no help, consider a fresh copy of OSX (that won't disturb anything else), per the same article.

I don't have two Macs that can run Lion, but I'll try to get some time to try it, both ways, between my iMac running Lion and my old G5 iMac running Leopard. Perhaps that will turn up something.

Not sure how much help it would be, but if you have AppleCare on either of your Macs, you might give AppleCare a try (800-275-2273) U.S. & Canada, or try the ExpressLane at https://expresslane.apple.com/.

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Answer 10

SMS5572 Author

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May 30, 2012 4:42 PM in response to Pondini

Tried a couple of other things as well as your suggestions above. Mo luck.

I tried changing the login user and password on the remote machine to my username and password on the local (destination) machine. Same result, although it did allow me to see and connect to all folders on my MAC PRO, as it should have.

The actual error message dialog box is slightly different than the one you provided previously, but essentially the same.

I'm getting very close to buying a seperate external drive for my wife's Mac. It's just that I hate to give up when I know this should work.

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Answer 11

Pondini

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May 30, 2012 4:51 PM in response to SMS5572

SMS5572 wrote:

Tried a couple of other things as well as your suggestions above. Mo luck.

Including the "combo" and fresh version of OSX? You're quick!

The actual error message dialog box is slightly different than the one you provided previously, but essentially the same.

Most folks get the other one, when they try to connect (before even trying to set up Time Machine).

I'm getting very close to buying a seperate external drive for my wife's Mac. It's just that I hate to give up when I know this should work.

You can always use another drive. 😉

Hoping to test with my old Mac later this evening. Maybe I can find something -- I'll keep you posted.

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Answer 12

SMS5572 Author

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May 30, 2012 4:54 PM in response to Pondini

Full disclosure. Everything BUT the fresh version of OSX. That sounds really scary to me. And I'm basically a coward. 😉

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Answer 13

Pondini

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May 30, 2012 5:09 PM in response to SMS5572

The 4+ GB download is a major pain, but otherwise it's easy.

It is a pretty long shot. Let's see if I can turn anything up in testing.

I did it in Snow Leopard, when writing the instructions. I'm pretty sure I tested it while beta-testing Lion a year ago, but can't swear to it (I know I didn't file any bug reports for it on Lion). I don't think I've tested it on 10.7.1 or later.

And, this is the only report of it I've seen (but there have been some periods of time when I didn't see every Lion thread here).

Message was edited by: Pondini

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Answer 14

etresoft

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May 30, 2012 7:09 PM in response to SMS5572

In my "dispute" with Pondini in the other thread, I came across some information that will certainly explain things, but not in a good way.

Apparently you cannot use an external drive as a Time Machine repository. People who use Snow Leopard and Lion Server to provide Time Machine services have already discovered this.

https://discussions.apple.com/thread/3327294

https://discussions.apple.com/thread/2472139

It may work better when your eSATA card comes in. My theory is that a Thunderbolt RAID would show up as an internal drive and would be useable as a Time Machine repository. There is a chance that an eSATA card would do that too. You'll find out. Apparently, one of the things you get with Lion Server is a warning pop-up if you try to use an external drive with Time Machine.

While I'm a big fan of Time Machine, I still consider it Apple Black Magic. You can use it, but don't get too clever. I don't like to take chances with backups. Simple is usually better. Time Machine isn't simple, but it is so convenient that I like to ignore the incredible complexity of it.

If the other machine were a notebook with local snapshots I might say you could manually plug it in to do backups. With two iMacs, I would recommend just getting another external drive.

Perilous to us all are the devices of an art deeper than we possess ourselves.

- Gandalf

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Answer 15

Pondini

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May 30, 2012 7:19 PM in response to etresoft

etresoft wrote:

. . .

Apparently you cannot use an external drive as a Time Machine repository. People who use Snow Leopard and Lion Server to provide Time Machine services have already discovered this.

Those refer to Lion Server, not Lion Client.

SMS5572 is running LION CLIENT, not Lion Server.

External HDs are by far the most common destination for Time Machine backups on OSX client Macs.

And the LOCAL backups work just fine. It's the network backups (of the iMac to the Pro) that don't.

Message was edited by: Pondini

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