[dm-devel] Clariion CX600 automatic failback support

[Christophe Varoqui]

On Fri, Nov 04, 2005 at 09:19:06AM +0100, Bernd Zeimetz wrote:
> Hi,
> 
> > Looks good, except the call to extract_hwe_from_path in setup_multipath
> > must be before the call to select_pgfailback.
> >
> 
> We have a ton of these log messages now.
> >From the last about 2 hours:
> 
> 580x multipathd: 3600601f4a20c000099dc229956b0d711: switch to path group #1
> 714x multipathd: 3600601f4a20c000096dc229956b0d711: switch to path group #1
> 714x multipathd: 3600601f2a20c0000fb13caa656b0d711: switch to path group #1
>   45x kernel: device-mapper: dm-emc: emc_pg_init: sending switch-over command
> 
> It happens only for these 3 of 8 luns.
> 
> Kernel is 2.6.13.4, devmapper 1.01, latest multipath-tools from git, evms 
> 2.5.3
> 
> zeus-1:/# cat /etc/multipath.conf
> defaults {
>         failback                                immediate
> }
> 
> 
> Since we had a lot of trouble with our CX400 (Hardware problems, but they're 
> supposed to be fixed) I'm wondering what these messages mean, and if we still 
> have hardware/software bugs somewhere.
> 
Yes, the test to determine if a switch is needed is sub-optimal :
The no activated PG case (all Enabled for exampleÃ) keeps triggering a switch.
I checked-in a patch to solve that issue.

Regards,
cvaroqui