Bug#700444: multipath-tools: Automatic path recovery not occurring on IBM Power with dual VIOS served disks.

[Frank Fegert]

Hello,

sorry for the delayed reply!

On Wed, Feb 13, 2013 at 11:47:00PM +0100, Frank Fegert wrote:
> > When you thought the paths were back, were they responding to scsi commands?
> 
> Sorry, didn't check that at the time.
> 
> > You could use tools from the sg3-utils package or use the scsi_id
> > program to  confirm that.
> 
> I'll try to setup a test environment.

In a test environment, after a consecutive reboot of each of the two
VIOS:

ststnagios02:~# multipath -ll
mpath0 (36005076801918127980000000000023b) dm-0 AIX,VDASD
size=36G features='0' hwhandler='0' wp=rw
`-+- policy='round-robin 0' prio=0 status=enabled
  |- 0:0:1:0 sda 8:0  failed faulty running
  `- 1:0:1:0 sdb 8:16 failed faulty running

ststnagios02:~# dmesg | tail
[6835466.341578] sd 0:0:1:0: [sda] CDB: Read(10): 28 00 00 00 00 00 00 00 08 00
[6835466.341592] end_request: I/O error, dev sda, sector 0
[6835467.341974] sd 1:0:1:0: [sdb] Unhandled error code
[6835467.341983] sd 1:0:1:0: [sdb]  Result: hostbyte=DID_ERROR driverbyte=DRIVER_OK
[6835467.341990] sd 1:0:1:0: [sdb] CDB: Read(10): 28 00 00 00 00 00 00 00 08 00
[6835467.342003] end_request: I/O error, dev sdb, sector 0
[6835471.342506] sd 0:0:1:0: [sda] Unhandled error code
[6835471.342516] sd 0:0:1:0: [sda]  Result: hostbyte=DID_ERROR driverbyte=DRIVER_OK
[6835471.342523] sd 0:0:1:0: [sda] CDB: Read(10): 28 00 00 00 00 00 00 00 08 00
[6835471.342536] end_request: I/O error, dev sda, sector 0

ststnagios02:~# /sbin/scsiinfo -l
/dev/sda /dev/sdb

ststnagios02:~# /sbin/scsiinfo -i /dev/sda
INQUIRY command status  = 1

ststnagios02:~# /sbin/scsiinfo -i /dev/sdb
INQUIRY command status  = 1

The Debian system is currently still in the "floating" state, so if
there's any other test you'd like me to run, that'd be no problem.
All other AIX systems on the test hardware sucessfully recovered their
paths though.

Thanks & best regards,

    Frank Fegert