apple/mac partition types support

ugluk · 2013-08-25 23:39:44

I am trying to mount an Apple partition created from a virtual machine and exported via nbd:

$ parted /dev/nbd0
WARNING: You are not superuser. Watch out for permissions.
GNU Parted 3.1
Using /dev/nbd0
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) p
Model: Unknown (unknown)
Disk /dev/nbd0: 10.7GB
Sector size (logical/physical): 512B/512B
Partition Table: mac
Disk Flags:

Number Start End Size File system Name Flags
1 512B 32.8kB 32.3kB Apple
2 32.8kB 10.2GB 10.2GB ext4 untitled
4 10.2GB 10.7GB 508MB swap swap

(parted)

But fdisk says:

$ fdisk /dev/nbd0
Welcome to fdisk (util-linux 2.23.2).

Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.

Device does not contain a recognized partition table
Building a new DOS disklabel with disk identifier 0xcf879138.

How can I mount the ext4 partition shown by parted? I've tried to load the hfs and hfsplus modules to no effect. Please help!

cfr · 2013-08-25 23:45:11

https://aur.archlinux.org/packages/hfsprogs/

ugluk · 2013-08-25 23:50:14

So I get fsck and mkfs, how is that supposed to help?

hfsprogs /usr/bin/fsck.hfsplus
hfsprogs /usr/bin/mkfs.hfsplus

ugluk · 2013-08-25 23:53:16

Also, hmount from hfsutils does not help

hmount /dev/nbd0 2
/dev/nbd0: contains 0 HFS partitions
hmount: /dev/nbd0: partition not found (Invalid argument)

cfr · 2013-08-26 00:05:35

You shouldn't need anything extra just to mount it but hfsprogs is useful if you want to mount at boot, say, because the system will look for a fsck tool. Though you can disable this.

hfsutils will not work with hfs+ partitions.

OK. I just reread your first post. Is this an ext4 partition as gparted claims? In that case, you should be able to mount it in the usual way and nothing fancy should be required at all. What have you tried?

ugluk · 2013-08-26 00:08:51

The thing is, that fdisk /dev/ndb0 should show me the 3 partitions, that gparted can recognize. If I cannot get fdisk to recognize those 3 partitions mounting the ext4 partition won't work. In my opinion the problem lies in a missing module for apple partition support. I would hate to have to compile a custom kernel though, that's why I ask here. Can I somehow download the missing module?

Last edited by ugluk (2013-08-26 00:09:11)

cfr · 2013-08-26 00:14:28

Are you certain fdisk can read the relevant partition table?

In fact, do you know what sort of partition table it is? I'm not sure what parted means by "mac". Does that mean Apple Partition Map? Or a newer type? Or something else?

gdisk can recognise APM but I can't find mention of that in fdisk's manual page.

ugluk · 2013-08-26 00:19:28

It is a partition table type that is used on PowerPC machines. I don't know how it is called. I suspect fdisk is using the kernel to query partition table info, while gparted reads the block device /dev/nbd0 directly and has built-in functionality.

cfr · 2013-08-26 00:25:16

OK. That's an Apple Partition Map. Or should be. Intel Macs use GPT but PPC Macs need APM to boot.

gdisk should be able to recognise that it is APM but not to manipulate the data.

Linux can definitely use APM - there shouldn't be anything odd about it that I can think of. You can install Linux on a disk with this type of partition map and it works fine. (I set a PPC mac up to dual boot OS X and GNU/Linux and it has to be APM for the former.)

ugluk · 2013-08-26 00:32:59

Sure it works, if it has the support compiled into the kernel, or as a module. I am on x86_64 arch linux and am trying to mount this mac partition, that's why I suspect it does not work.

cfr · 2013-08-26 00:54:13

If you are using the stock kernel, it supports it, I think. I am pretty sure that

CONFIG_MAC_PARTITION=y

is referring to APM.

ugluk · 2013-08-26 12:55:47

This was the solution:

# parted /dev/nbd0
GNU Parted 3.1
Using /dev/nbd0
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) p
Model: Unknown (unknown)
Disk /dev/nbd0: 10.7GB
Sector size (logical/physical): 512B/512B
Partition Table: mac
Disk Flags:

Number Start End Size File system Name Flags
1 512B 32.8kB 32.3kB Apple
2 32.8kB 10.2GB 10.2GB ext4 untitled
3 10.2GB 10.7GB 508MB swap swap

(parted) unit B
(parted) p
Model: Unknown (unknown)
Disk /dev/nbd0: 10737418240B
Sector size (logical/physical): 512B/512B
Partition Table: mac
Disk Flags:

Number Start End Size File system Name Flags
1 512B 32767B 32256B Apple
2 32768B 10229033471B 10229000704B ext4 untitled
3 10229033472B 10737417727B 508384256B swap swap

(parted) q
# mount -o loop,offset=32768 /dev/nbd0 /mnt

srs5694 · 2013-08-26 15:15:12

You may have solved this problem to your satisfaction, but I have two additional suggestions:

There's a command or method to cause the kernel to create partition device files. Unfortunately, I don't recall the details offhand. I vaguely recall setting this up as a udev rule once, so it may be something that's built into udev; or it could be I launched an external command using a udev rule. Either way, try doing a Web search on "Linux create partition device files" or something similar. In fact, it's conceivable that these files already exist; you can search for /dev/nbd0*; if there are additional files (like /dev/nbd01, /dev/nbd02, and /dev/nbd03), they refer to the partitions on the device.
Export only the partition you want. I don't know what software you're using on the Mac side, but if it's even remotely flexible, it should provide a way for you to export partition 2 on the target disk without exporting the whole disk. This is likely to be the simplest solution, assuming the software on the Mac side supports this.

Arch Linux

#1 2013-08-25 23:39:44

apple/mac partition types support

#2 2013-08-25 23:45:11

Re: apple/mac partition types support

#3 2013-08-25 23:50:14

Re: apple/mac partition types support

#4 2013-08-25 23:53:16

Re: apple/mac partition types support

#5 2013-08-26 00:05:35

Re: apple/mac partition types support

#6 2013-08-26 00:08:51

Re: apple/mac partition types support

#7 2013-08-26 00:14:28

Re: apple/mac partition types support

#8 2013-08-26 00:19:28

Re: apple/mac partition types support

#9 2013-08-26 00:25:16

Re: apple/mac partition types support

#10 2013-08-26 00:32:59

Re: apple/mac partition types support

#11 2013-08-26 00:54:13

Re: apple/mac partition types support

#12 2013-08-26 12:55:47

Re: apple/mac partition types support

#13 2013-08-26 15:15:12

Re: apple/mac partition types support

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