[dm-devel] Re: Problems using multipath-tools & dm-multipath.

[christophe.varoqui at free.fr]

don't apply patch 00008+ in udm patch-set :
they break the dm event subsystem

regards,
cvaroqui

Selon "Caushik, Ramesh" <ramesh.caushik at intel.com>:

>
> I am trying to use multipath-tools version 0.2.7 on a system running
> 2.6.6 kernel with the 2.6.6-rc2-udm1 dm patchset. The system has dual
> port Qlogic 2312 controller, connected to a JBOD through a FC switch.  I
> have the multipath drives configured as follows
>
> - path_grouping_policy multibus
> - getuid_callout    /bin/scsi_id -g -s
> - path_checker    tur
>
> I start multipathd; run multipath; run kpartx on a partioned drive dm-7
> (this results in additional devmaps dm-11 & dm-12); I then run bonnie++
> on the partition dm-11. While bonnie++ is in progress I disconnect one
> of the FC ports from the switch. I expect
>
> -- the path switch to happen and the failed bios to be retried so the
> application can run after a delay.
>
> I find that the application waits for a long while, reports an I/O error
> and quits. The behaviour is not different with other applications that
> access the drive.
> Is this supposed to work ? What could be the problem here ?
>
> Secondly I connect the port back to the switch. I expect the path
> re-connect to be discovered and the multipath device map to be restored.
> But subsequent disk I/O through the same devmapped device (dm-11) sends
> data only through one port (one that has always been connected). The
> path restoration does not happen. Do you have thoughts on these.
> Appreciate your feedback on this,
>
> Ramesh.
>
>
>


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