Fwd: multipath errors

[Amitai Alkalay <amitai.alkalay.work@xxxxxxxxx>]

Hi,

Sorry for bumping, but I will appreciate any help on this matter..

Thanks,

Amitai

---------- Forwarded message ----------
From: Amitai Alkalay <amitai.alkalay.work@xxxxxxxxx>
Date: Tue, Sep 10, 2013 at 2:29 PM
Subject: multipath errors
To: dm-devel@xxxxxxxxxx

hi,

I sometimes see cases where io failed after some path failover, although there are other valid paths.

I seem to get a lot of the following errors during a path removal (failover):

Aug  1 08:59:37 lg641 multipathd: 3514f0c532d80000a: failed in domap for removal of path sdcy
Aug  1 08:59:37 lg641 multipathd: uevent trigger error
Aug  1 08:59:37 lg641 multipathd: sdt: remove path (uevent)
Aug  1 08:59:37 lg641 kernel: device-mapper: table: 253:5: multipath: error getting device
Aug  1 08:59:37 lg641 kernel: device-mapper: ioctl: error adding target to table
Aug  1 08:59:37 lg641 multipathd: 3514f0c532d800001: load table [0 21474836480 multipath 0 0 1 1 queue-length 0 12 1 66:240 1 66:80 1 70:192 1 71:96 1 67:176 1 67:112 1 71:224 1 128:128 1 8:
16 1 69:16 1 69:32 1 8:32 1]
Aug  1 08:59:37 lg641 multipathd: sdt: path removed from map 3514f0c532d800001f

All the other paths are there, and still multipath decided to fail the io with no apparent reason. 

I would appreciate any comment about:

1. How can this happen.
2. How can I increase the log level to understand multipath decisions.
3. Why do I always see the errors regarding adding target to table.
The only thing I can think think about, that multipath temporarily bypassed the other paths (maybe it got busy several times and gave up).

I'm using device-mapper-multipath-0.4.9-64.el6.x86_64.

Thanks a lot,

Amitai

--
dm-devel mailing list
dm-devel@xxxxxxxxxx
https://www.redhat.com/mailman/listinfo/dm-devel