topic Re: duplicate PV's in Operating System - Linux

duplicate PV's

MikeL_4 — Tue, 07 Apr 2009 18:46:38 GMT

When doing pvdisplay or vgdisplay we are receiving Duplicate PV messages:

# pvdisplay
Found duplicate PV z2H9sLDn5qc44YWGlAfSOGaSZulp6HwP: using /dev/sdc1 not /dev/sdag1
Found duplicate PV BMLZu8q46LcDMcQasb56v1lLMVnGRcNF: using /dev/sdd1 not /dev/sdah1
Found duplicate PV bcKTYbZEoBqobw4idMokNoLiI7cSJAG8: using /dev/sde1 not /dev/sdai1
Found duplicate PV U1118tNzain3ITt4h2T0LB4ZvvGmv553: using /dev/sdf1 not /dev/sdaj1
Found duplicate PV Xz3FTA3N5A28cCgXkryKpsKPcY3vtY1x: using /dev/sdg1 not /dev/sdak1
Found duplicate PV u4a3f9lsUo2zcpS7wNYX8FF5EPgTsOSe: using /dev/sdk1 not /dev/raw4
Found duplicate PV 97tZYWlAe8OhwnY9iCEizfzWxjDmWHt0: using /dev/sdm1 not /dev/raw6
Found duplicate PV gqH0mwzqrUfO0i7oKXtBOCA3SGOelrwr: using /dev/sdn1 not /dev/raw7
Found duplicate PV cjLWzqVPsISfDXaAkQi75aLjpJaxm3F0: using /dev/sdp1 not /dev/raw9
Found duplicate PV 7X8MMy2ffjsV0QAWg3AzMkr56h8GsNqo: using /dev/sdaf1 not /dev/sdb1

These are on SAN attached devices and I assume it's due to having two Fibre cards to the SAN for the same LUN's...

Is there a way to resolve this issue ??

Re: duplicate PV's

smatador — Tue, 07 Apr 2009 19:50:51 GMT

Hi,
Do you have powerpath or a multipath tool, if not maybe you could install?

Nevertheless, you could create a filter in /etc/lvm/lvm.conf so that lvm will ignore the devices.
Look at the filter section on lvm.conf, for example
http://www.redhat.com/docs/manuals/csgfs/browse/4.6/Cluster_Logical_Volume_Manager/lvmconf_file.html
Hope it helps

Re: duplicate PV's

MikeL_4 — Wed, 08 Apr 2009 11:58:08 GMT

Thanks, I ended up using Red Hat's Multipath to resolve the issue....

Re: duplicate PV's

skt_skt — Fri, 10 Apr 2009 14:04:01 GMT

I have a problem with multipath..
"Buffer IO" mmessages are appearing in messages file for standby paths/devices.

Apr 5 23:00:02 hrdl2d kernel: Device sdb not ready.
Apr 5 23:00:02 hrdl2d kernel: end_request: I/O error, dev sdb, sector 0
Apr 5 23:00:02 hrdl2d kernel: Buffer I/O error on device sdb, logical block 0
Apr 5 23:00:02 hrdl2d kernel: Device sdb not ready.
Apr 5 23:00:02 hrdl2d kernel: end_request: I/O error, dev sdb, sector 0
Apr 5 23:00:02 hrdl2d kernel: Buffer I/O error on device sdb, logical block 0
Apr 5 23:00:02 hrdl2d kernel: Device sdb not ready.
Apr 5 23:00:02 hrdl2d kernel: end_request: I/O error, dev sdb, sector 0

In the below o/p "1" indicates the current/active paths.

Red Hat Enterprise Linux AS release 4 (Nahant Update 7)

Linux hstname 2.6.9-78.ELsmp #1 SMP Wed Jul 9 15:46:26 EDT 2008 x86_64 x86_64 x86_64 GNU/Linux

device-mapper-multipath-0.4.5-31.el4
~]# multipathd -k show config
multipathd> show paths

#:#:#:# hdc 22:0 [faulty] [orphan]
3:0:0:0 sdb 8:16 [active][ready] X................... 1/20
3:0:0:1 sdc 8:32 [active][ready] X................... 1/20
3:0:0:2 sdd 8:48 1 [active][ready] X................... 1/20
3:0:0:3 sde 8:64 [active][ready] X................... 1/20
3:0:1:0 sdf 8:80 1 [active][ready] X................... 1/20
3:0:1:1 sdg 8:96 1 [active][ready] X................... 1/20
3:0:1:2 sdh 8:112 [active][ready] X................... 1/20
3:0:1:3 sdi 8:128 1 [active][ready] X................... 1/20

multipathd>

Do you see the similar problems? Or i have a configuration issue??

Re: duplicate PV's

MikeL_4 — Fri, 10 Apr 2009 14:21:38 GMT

No, I am not seeing any error messages in my log file..