MBR partition table (instead of GPT) on Intel Mac okay for SD? [Archive]

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pmocek

12-29-2006, 07:35 PM

I'm using Mac OS X 10.4 on Intel hardware. The machine has an MBR (http://en.wikipedia.org/wiki/Master_boot_record) partition table instead of the default partition table type, GPT (http://en.wikipedia.org/wiki/GUID_Partition_Table), so that I can more easily run other operating systems on it.

I am able to successfully clone to another partition, but Superduper fails when it attempts to mark the other partition ("volume") as bootable.

Is Superduper compatible with MBR partition tables?

dnanian

12-29-2006, 07:39 PM

We don't really care what the partition scheme is, but OSX might. I'd need to see the error to attempt any kind of diagnosis, though.

pmocek

12-29-2006, 08:00 PM

dnanian

12-29-2006, 08:23 PM

I need the whole thing, not just a clip.

pmocek

12-29-2006, 08:31 PM

I need the whole thing, not just a clip.

Hmm... It's pretty long and I'd have to read the whole thing to make sure there's no personal information in there before I go posting it on the Interwebs. Is there some particular part (besides that which shows the error and associated codes, which I have already posted) that you need to see in order to diagnose?

dnanian

12-29-2006, 08:37 PM

Feel free to send it to me at the support address. But I do need the whole thing.

pmocek

12-29-2006, 08:40 PM

Is it saved somewhere, or do I need to run another clone? (I closed Superduper after running it to get the error code you requested.)

dnanian

12-29-2006, 08:48 PM

Open SuperDuper!, press Cmd+L, then "Send to shirt pocket..."

pmocek

12-29-2006, 08:57 PM

dnanian

12-29-2006, 09:00 PM

Quite weird. So, you're updating a 10.4.8 volume with a 10.4.6 install... something weird clearly happened. Can you try an erase-then-copy rather than a Smart Update to see if that works?

pmocek

12-29-2006, 09:16 PM

you're updating a 10.4.8 volume with a 10.4.6 install

Oh. Oops. No, actually I applied the 10.4.8 update to the clone partition after creating it with Superduper and receiving the same error. I just ran it again today so I could get the error code for you.

dnanian

12-29-2006, 10:48 PM

OK. But could you try an erase-then-copy to see what that does?

pmocek

12-30-2006, 12:29 AM

dnanian

12-30-2006, 10:53 AM

This is quite peculiar, pmocek. It's almost like you're running on a non-Apple computer. Possible?

pmocek

12-31-2006, 12:44 PM

It's almost like you're running on a non-Apple computer. Possible?

Well, depending on how you define "non-Apple" it's beyond possible -- it's a fact. As I said before: this is not a stock machine. I have changed the partition table from GPT to MBR in order to more effectively boot multiple operating systems. GPT is fairly new, and many other operating systems don't yet handle it properly. It's a better system, in my opinion, but I'll stick with the old one if doing so will make OS X to play nicely with GNU/Linux and others.

Is Superduper restricted to use with machines using GPT partition tables when running on OS X on Intel hardware?

Truth be told, I have had trouble getting the cloned partition set as a startup disk. But I would think that if Superduper cannot do so, Shirt Pocket would prefer it to recognize this and then issue a warning, refuse to run until the option to set as startup disk is disabled, etc., instead of running all the way through the backup then failing with a cryptic error message. The latter is definitely not consistent with Superduper's otherwise excellent UI.

So, any clues? I realize this is a corner-case for now, but I'm confident that with time you'll find yourselves with more customers running OS X on newer hardware, and more of us Unix geeks jumping on the bandwagon, pushing the boundaries of OS X and Superduper in the process.

dnanian

12-31-2006, 12:56 PM

Well, more than just a non-stock machine: this isn't Apple hardware at all, right? It's just a generic box you've managed to get OSX working on, no? (I don't mean this in a disparaging way, I just want to confirm the situation that I can't reproduce on any of the hardware I have here: this is not a standard OSX install, regardless of partition type.)

This has nothing to do with MBR: it's because the source partition doesn't have the proper standard configuration to be bootable in a standard way (for example, it doesn't have BootX in the right place). The files have been copied, and you'll have to repeat whatever you did to get the source partition booted on the destination.

pmocek

12-31-2006, 01:35 PM

this isn't Apple hardware at all, right? It's just a generic box you've managed to get OSX working on, no? I'm not the original owner, so I can't trace all the parts that make up this computer back to their manufacture (and does Apple manufacture its own hardware, anyway?) but for all practical purposes, yes, you're correct.

This has nothing to do with MBR Sorry for the confusion. I wasn't really referring to the master boot record, I meant "the MBR partition table scheme" as opposed to "the GPT (GUID partition table) scheme".

it's because the source partition doesn't have the proper standard configuration to be bootable in a standard way Hmm... I believe it is booting in the standard way, but on a proprietary OS, it's really hard to tell what's going on, so I can't say for sure. (Oh, how I miss the thorough documentation that often comes with free software (http://www.gnu.org/philosophy/free-sw.html).)

If you want to test for this situation with "stock" Apple hardware, you could: Start with a new, un-partitioned hard disk in an Intel-processor-based Mac
Create some partitions on it with something other than Apple's Disk Utility, such as fdisk, cfdisk, or sfdisk on GNU/Linux, possibly from a "live CD" distribution like KNOPPIX Linux (http://www.knopper.net/knoppix/index-en.html) (mine has three primary partitions and an extended partition that contains several others)
Perform a standard installation of Mac OS X to one of the primary partition (I installed to the third one)
Clone to another primary (mine: second), and tell Superduper to set that one as the startup disk

(FYI, I use a registered copy of Superduper on a Pismo all the time and am thoroughly satisfied with it when used for that purpose.)

dnanian

12-31-2006, 03:39 PM

Really, there was no need to be coy about this, and you could have saved us both a lot of time -- and me a lot of testing -- if you had just indicated this wasn't a real Mac in the first place.

Anyway, no, I just can't spend the time necessary to try to reproduce this situation -- once you step off the standards, you're kind of on your own. Sorry -- it's hard enough dealing with all the Macs that do get released to start dealing with non-Apple hardware with a nonstandard partitioning scheme (Disk Utility will partition with MBR, FYI) created with nonstandard tools, etc.

As I indicated, your configuration doesn't have a BootX file in the proper place, so it's not going to be seen as a standard System folder and isn't going to bless properly. But if you mess about with it appropriately perhaps you'll be able to get it to work; feel free to indicate to others how you managed it, in this thread -- should they encounter a similar situation, they'll at least find this documentation.

pmocek

12-31-2006, 03:54 PM

Sorry -- didn't mean to be coy. When asking for help with software, I try to pare down the details to just those that I believe to be necessary to reproduce the behavior, rather than just dumping everything I know and letting others sort out the details.

Can you point me to documentation of Superduper's requirement that a BootX file be in the proper place? The Superduper User's Guide does not include the word "bootx".

dnanian

12-31-2006, 03:58 PM

It's not our requirement. It's OSX's.

pmocek

12-31-2006, 04:06 PM

I just did a quick Web search and found that BootX is only used with PowerPC-processor-based Macs (http://developer.apple.com/documentation/MacOSX/Conceptual/BPSystemStartup/Articles/BootProcess.html). Those with Intel CPUs don't use BootX.

So the lack of existence of BootX must not be the problem in this case.

dnanian

12-31-2006, 04:10 PM

Not really relevant: BootX is present for all Macs.