Red Hat Bugzilla – Bug 871940
grub2-install does not work on multipath
Last modified: 2015-05-12 16:44:06 EDT
14:31:21,468 INFO program: Running... grub2-install --no-nvram --no-floppy /dev/mapper/mpatha1
14:31:22,459 ERR program: /usr/sbin/grub2-probe: warning: unknown device type dm-3
14:31:22,459 ERR program: .
14:31:22,497 ERR program: The chosen partition is not a PReP partition.
Device Boot Start End Blocks Id System
/dev/mapper/mpatha1 * 2048 10239 4096 41 PPC PReP Boot
/dev/mapper/mpatha2 10240 1034239 512000 83 Linux
/dev/mapper/mpatha3 1034240 7129087 3047424 82 Linux swap / Solaris
/dev/mapper/mpatha4 7129088 31457279 12164096 5 Extended
/dev/mapper/mpatha5 7131136 31457279 12163072 83 Linux
[anaconda root@riley6 ~]# chroot /mnt/sysimage/
[anaconda root@riley6 /]# grub2-install --no-nvram --no-floppy /dev/mapper/mpatha1
/usr/sbin/grub2-probe: warning: unknown device type dm-3
The chosen partition is not a PReP partition.
[anaconda root@riley6 /]# grub2-probe /dev/mapper/mpatha1
grub2-probe: error: failed to get canonical path of devtmpfs.
[anaconda root@riley6 /]# grub2-probe -d /dev/dm-3
This is running on anaconda-18.21-1 with the following patches:
I should also mention that anaconda is now running kpartx without the "-p p" option.
This is caused by malformed device UUIDs.
Grub2 relies on dm UUID to identify a multipath device and also to differentiate a multipath device from its partitions.
You can get the UUID of the partition by running the following command:
dmsetup info /dev/mapper/mpatha1
The first partition on a multipath device should have a UUID like:
However, for some reason, when anaconda creates the partitions on a multipath disk, the partitions get assigned a UUID like:
Note the 'p1' at the end of the UUID.
Grub2 should work fine if the multipath devices get assigned proper UUID's.
moving to F18Blockerppc
As Gustavo mentioned, this seems to have been a leftover uuid issue and not a multipath problem in itself.
Closing this bug then as NOTABUG.
Thanks & regards, Phil