[Linux-cluster] qdisk and multipathing problems

[Jos Vos]

On Tue, Oct 31, 2006 at 12:58:47PM +0200, Riaan van Niekerk wrote:

> <quorumd interval="1" tko="10" votes="2" device="/dev/emcpowera1" 
> label="quorum_disk_1">
>   <heuristic program="ping 192.168.222.254 -c1 -t1" score="2" interval="2"/>
> </quorumd>
> 
> I tell it to use /dev/emcpowera1 but it insists on using the first path, 
>   /dev/sdc1
> 
> [...]
> 
> Is there any way to blacklist /dev/sd* devices from being scanned 
> (similar to what is done for LVM)? or force qdisk to use /dev/emcpowera1?

I think you should use device=... *or* label=..., not both.  So with
multipath problems, you need to use only device=...

Unfortunately, behavior of qdiskd and mount differs a lot in the way
they handle device scanning to search for labels :-(.  Qdiskd just
sequentially scans *everything* in /proc/partitions, while mount does
honour /etc/fstab.order, but on its turn only scans devices ending on
a digit (partitions), which can be quite annoying.  A bit of a mess,
IMHO, and the behaviour of both mount and qdiskd can be improved for
more consistency and flexibility.

-- 
--    Jos Vos <jos at xos.nl>
--    X/OS Experts in Open Systems BV   |   Phone: +31 20 6938364
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