This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
Home Products Support Community News


[Xen-users] xen: when devices go away...

To: xen-users@xxxxxxxxxxxxxxxxxxx
Subject: [Xen-users] xen: when devices go away...
From: Steve Wray <steve.wray@xxxxxxxxx>
Date: Fri, 02 Feb 2007 13:59:47 +1300
Delivery-date: Thu, 01 Feb 2007 17:00:09 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
List-help: <mailto:xen-users-request@lists.xensource.com?subject=help>
List-id: Xen user discussion <xen-users.lists.xensource.com>
List-post: <mailto:xen-users@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Thunderbird (X11/20060813)
Hi there,
I've been experimenting with iscsi and xen and have found an interesting

I'd reasoned that using iscsi volumes as devices in a software RAID1
configuration would be a Good Idea since when one of the iscsi servers
goes away the filesystem is stable.

I have a dom0 which has access to two iscsi volumes on two seperate
iscsi target servers.

I configure a domU with these two iscsi targets as its block devices, ie:

disk = [ 'phy:iscsi/iqn.2006-12.server1:raid/lun0/part,sda1,w',
        'phy:iscsi/iqn.2006-12.server2:raid/lun0/part,sdb1,w' ]

root = "/dev/md0 ro"

This works in as much as the domU has root on a RAID1 md device and it
functions normally; until I shutdown one of the iscsi servers. At that
point the domU dies horribly. I see no messages on the domU console at
all and so far nothing on the dom0 console either.

Nothing in any of the logs. I also don't see anything noteworthy in xm
log nor xm dmesg when this happens; the domU becomes unresponsive and
has to be killed with xm destroy.

Am I expecting too much? Will xen just not cope when one of the block
devices handed out to a domU simply 'goes away'?

iscsi aside, what would xen be expected to do if you had two scsi
drives, sda and sdb, presented to a domU as vbd's and used by the domU
in a RAID1 array... ie what would xen do if one of those hard drives failed?


Xen-users mailing list

<Prev in Thread] Current Thread [Next in Thread>