[dm-devel] Unstable isci path and confusing logging

[Charlie Brady]

On Fri, 3 Jul 2009, Charlie Brady wrote:

> Jul  3 12:29:59 sun4150node2 multipathd: sdc: rdac checker reports path is up
> Jul  3 12:30:04 sun4150node2 multipathd: sdc: rdac checker reports path is up
> Jul  3 12:30:09 sun4150node2 multipathd: sdc: rdac checker reports path is up
> Jul  3 12:30:14 sun4150node2 multipathd: sdc: rdac checker reports path is up
> Jul  3 12:30:19 sun4150node2 multipathd: sdc: rdac checker reports path is up
> Jul  3 12:30:24 sun4150node2 multipathd: sdc: rdac checker reports path is up
> Jul  3 12:30:29 sun4150node2 multipathd: sdc: rdac checker reports path is up
> [root at sun4150node2 ~]#

This is the cycle of multipathd failing and reinstating the device:

[root at sun4150node2 ~]# grep 8:32 /var/log/messages | tail -12
Jul  3 12:57:38 sun4150node2 multipathd: 8:32: reinstated
Jul  3 12:57:38 sun4150node2 kernel: device-mapper: multipath: Failing path 8:32.
Jul  3 12:57:39 sun4150node2 multipathd: 8:32: mark as failed
Jul  3 12:57:43 sun4150node2 multipathd: 8:32: reinstated
Jul  3 12:57:44 sun4150node2 kernel: device-mapper: multipath: Failing path 8:32.
Jul  3 12:57:44 sun4150node2 multipathd: 8:32: mark as failed
Jul  3 12:57:48 sun4150node2 multipathd: 8:32: reinstated
Jul  3 12:57:50 sun4150node2 kernel: device-mapper: multipath: Failing path 8:32.
Jul  3 12:57:50 sun4150node2 multipathd: 8:32: mark as failed
Jul  3 12:57:53 sun4150node2 multipathd: 8:32: reinstated
Jul  3 12:57:53 sun4150node2 kernel: device-mapper: multipath: Failing path 8:32.
Jul  3 12:57:54 sun4150node2 multipathd: 8:32: mark as failed
[root at sun4150node2 ~]#

> As further background, I have four iscsi paths configured to two ports on two 
> controllers on a Sun StorageTek 2510 (a bug in the Sun CAM management 
> software has also configured a non-working IPV6 session).

On a related issue, is there any way to learn which of the iscsi paths 
is associated with which device node (/dev/sdX)?