[Linux-cluster] Get qdisk to use /dev/mapper/mpathx devices insteadof /dev/dm-x

Kit Gerrits kitgerrits at gmail.com
Thu May 6 00:01:57 UTC 2010


The danger in using /dev/dm-x is that there is no guarantee that the same
device will show up at the same place after a reboot.
Seeing as you use disklabels, this becomes a non-issue.

Aside from that, I am not aware of any other reasons not to use /dev/dm-x

-----Original Message-----
From: linux-cluster-bounces at redhat.com
[mailto:linux-cluster-bounces at redhat.com] On Behalf Of Don Hoover
Sent: woensdag 5 mei 2010 20:03
To: linux-cluster at redhat.com
Subject: [Linux-cluster] Get qdisk to use /dev/mapper/mpathx devices
insteadof /dev/dm-x

I have recently learned that its dangerous to use /dev/dm-x devices for LVM
because they do not function correctly with multipath, and that you should
always use the /dev/mapper/mpathx devices.  Something about the fact that
udev actually destroys and recreates the dm devices when paths change.

But, qdisk seems to prefer using dm-x devices.  Is there a way to get it to
prefer using /dev/mapper/mpathx devices if they are available?

I know you can spec the device instead of the label, but I would like to
avoid that.



--
Linux-cluster mailing list
Linux-cluster at redhat.com
https://www.redhat.com/mailman/listinfo/linux-cluster
No virus found in this incoming message.
Checked by AVG - www.avg.com
Version: 9.0.814 / Virus Database: 271.1.1/2853 - Release Date: 05/05/10
08:26:00




More information about the Linux-cluster mailing list