Bug#567019: kpartx: multipath partition devices are missing

[Guido Günther]

On Tue, Jan 26, 2010 at 07:06:26PM +0100, Ferenc Wagner wrote:
> Package: kpartx
> Version: 0.4.8-14+lenny2
> Severity: normal
> 
> Hi,
> 
> I'd like to boot from a partitioned multipath device, but the device nodes
> corresponding to the partitions aren't created.  At the (initramfs) prompt:
> 
> (initramfs) multipath -ll
> nfs (360060160ec612000f6f237e09406df11) dm-0 DGC     ,RAID 5        
> [size=5.0G][features=1 queue_if_no_path][hwhandler=1 emc]
> \_ round-robin 0 [prio=2][active]
>  \_ 1:0:1:0 sdb 8:16  [active][ready]
>  \_ 0:0:1:0 sdd 8:48  [active][ready]
> \_ round-robin 0 [prio=0][enabled]
>  \_ 1:0:0:0 sda 8:0   [active][ready]
>  \_ 0:0:0:0 sdc 8:32  [active][ready]
> 
> which looks perfectly good, but
> 
> (initramfs) ls -l /dev/disk/by-id
> lrwxrwxrwx    1 0        0              16 Jan 26 17:38 dm-name-nfs -> ../../mapper/nfs
> lrwxrwxrwx    1 0        0              16 Jan 26 17:38 dm-uuid-mpath-360060160ec612000f6f237e09406df11 -> ../../mapper/nfs
> lrwxrwxrwx    1 0        0               9 Jan 26 17:50 scsi-360060160ec612000f6f237e09406df11 -> ../../sda
> lrwxrwxrwx    1 0        0              10 Jan 26 17:38 scsi-360060160ec612000f6f237e09406df11-part1 -> ../../sdd1
> lrwxrwxrwx    1 0        0              10 Jan 26 17:38 scsi-360060160ec612000f6f237e09406df11-part2 -> ../../sdd2
> lrwxrwxrwx    1 0        0               9 Jan 26 17:38 scsi-SIBM-ESXSST936701LC_F3LC065GL00007604NMST -> ../../sde
> lrwxrwxrwx    1 0        0              10 Jan 26 17:38 scsi-SIBM-ESXSST936701LC_F3LC065GL00007604NMST-part1 -> ../../sde1
> lrwxrwxrwx    1 0        0              10 Jan 26 17:38 scsi-SIBM-ESXSST936701LC_F3LC065GL00007604NMST-part2 -> ../../sde2
> lrwxrwxrwx    1 0        0               9 Jan 26 17:50 wwn-0x60060160ec612000 -> ../../sda
> lrwxrwxrwx    1 0        0              10 Jan 26 17:38 wwn-0x60060160ec612000-part1 -> ../../sdd1
> lrwxrwxrwx    1 0        0              10 Jan 26 17:38 wwn-0x60060160ec612000-part2 -> ../../sdd2
> 
> which feels rather confused (sd[a-d] are the paths, sde is a local disk).
> Basically, I miss dm-name-nfs-part[12] and the corresponding /dev/mapper/nfs-part[12]
> devices.
> 
> (initramfs) kpartx -l /dev/mapper/nfs
> nfs1 : 0 385497 /dev/mapper/nfs 63
> nfs2 : 0 10088820 /dev/mapper/nfs 385560
> 
> which is about right, kpartx -a /dev/mapper/nfs; vgchange -ay nfs lets the boot
> conclude normally (/dev/mapper/nfs2 is my PV), although /dev/mapper/nfs1
> disappears, so later I get
> 
> Checking file systems...fsck from util-linux-ng 2.16.2
> fsck.ext2: Bad magic number in super-block while trying to open /dev/mapper/nfs1
> 
> but that's probably the same issue striking again.
> /lib/udev/rules.d/60-kpartx.rules is in place and should work, but somehow it
> does not.  At least the above device/partition mixup is not present in the booted
> system:
> 
> lrwxrwxrwx 1 root root  9 2010-01-26 18:58 scsi-360060160ec612000f6f237e09406df11 -> ../../sdd
> lrwxrwxrwx 1 root root 10 2010-01-26 18:57 scsi-360060160ec612000f6f237e09406df11-part1 -> ../../sdd1
> lrwxrwxrwx 1 root root 10 2010-01-26 18:57 scsi-360060160ec612000f6f237e09406df11-part2 -> ../../sdd2
> lrwxrwxrwx 1 root root  9 2010-01-26 18:58 wwn-0x60060160ec612000 -> ../../sdd
> lrwxrwxrwx 1 root root 10 2010-01-26 18:57 wwn-0x60060160ec612000-part1 -> ../../sdd1
> lrwxrwxrwx 1 root root 10 2010-01-26 18:57 wwn-0x60060160ec612000-part2 -> ../../sdd2
> 
> Interestingly,
> 
> lrwxrwxrwx 1 root root 17 2010-01-26 18:57 /dev/disk/by-id/dm-name-nfs1 -> ../../mapper/nfs1
> 
> is also present, although broken in the booted system.
> Udev changed a lot since Lenny, I'd appreciate some help finding the problem.
Could you add a "sleep 10" at the end of the multipath local-top
initramfs script?  It's possible that lvm "grabs" the sd* devices before
multipath had a chance to assemble the multipath maps. That would at
least look like the above.
Cheers,
 -- Guido