Re: [dm-devel] multipath-tools with STK FLEXLINE 380

[Hannes Reinecke <hare suse de>]

Tony Lapointe wrote:
>                 Do not use 'rr_weight=priorities'. The priorities
>                 handling is currently buggered; or, put it the other way
>                 round, you will need at least my latest fix to get it
>                 working. Just remove that line and stay with the
>                 defaults. That should work.
>                 
>                 And as a sidenote: Using 'group_by_prio' and
>                 'rr_weight=priorities' is completely pointless, even if
>                 'rr_weight=priorities' should be working.'group_by_prio'
>                 will lump all devices with the same priority into one
>                 group. And 'rr_weight=priorities' will then modify the
>                 'minio' based on the priority. So you can as well
>                 directly modify the 'minio'
>                 parameter.'rr_weight=priorities' only makes sense if you
>                 have path with different priorities in one group, ie
>                 when using 'multibus' or 'group_by_serial'.
>                 Cheers,
>                 
>                 Hannes
>                 --
>                 Dr. Hannes Reinecke			hare suse de
>                 SuSE Linux Products GmbH		S390 & zSeries
>                 Maxfeldstraße 5				+49 911 74053 688
>                 90409 Nürnberg				http://www.suse.de
>
>
>
>
> Hi Hannes,
>
> thanks for the reply.
>
> I've tried without "rr_weight=priorities" in my multipath.conf but  it does
> not work either.
> The only difference it makes is that "multipath -v3" now output : 
> "rr_weight = 1 (internal default)"
> instead of "rr_weight = 2 (config file default)".
>
> I was thinking that "group_by_prio" is use to group together devices with
> differents priorities, with the one with the highest priority first, 
is it wrong?
>
Yes. It groups devices with _identical_ priorities together.

> The output of "multipath -d -v2" seems to reflect this :
[ .. ]

The output is correct. You have two paths to each disk, and each path 
has a different priority. So the multipath topology is correct.

Cheers,

Hannes
--
Dr. Hannes Reinecke			hare suse de
SuSE Linux Products GmbH		S390 & zSeries
Maxfeldstraße 5				+49 911 74053 688
90409 Nürnberg				http://www.suse.de