WARNING - OLD ARCHIVES

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/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-users

Re: [Xen-users] iscsi conn error: Xen related?

To: Tomasz Chmielewski <mangoo@xxxxxxxx>
Subject: Re: [Xen-users] iscsi conn error: Xen related?
From: Fred Blaise <fred.blaise@xxxxxxxxxxx>
Date: Tue, 06 May 2008 14:17:00 +0200
Cc: Xen-users@xxxxxxxxxxxxxxxxxxx
Delivery-date: Tue, 06 May 2008 05:17:32 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
In-reply-to: <482037C2.1030109@xxxxxxxx>
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>
References: <481F27EB.5030106@xxxxxxxxxxx> <481F2AA8.4000603@xxxxxxxx> <48203596.3060603@xxxxxxxxxxx> <482037C2.1030109@xxxxxxxx>
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Thunderbird 2.0.0.12 (X11/20080226)
Tomasz Chmielewski wrote:
Fred Blaise schrieb:
Hey Thomasz,

I could get an interesting and clear trace when things started going south this morning... for no appearant reason (ie: no load). Load shouldn't be a problem is this environment yet.

Starting with nop-out timing out.. then sank from there to fail all I/O.

Does it by chance happen about when you restart your iSCSI initiators or disconnect briefly?
I'm not sure what e-open uses, but here is some read about it:

http://blog.wpkg.org/2007/09/09/solving-reliability-and-scalability-problems-with-iscsi/
Good read. Thanks for that.


I indeed also opened a ticket with open-e, but haven't gotten an answer yet.

I also launched a ping -s 8192 -i 3 -I ethXX to the storage, to see if I am losing icmp packets when the iscsi connections are lost.

And?
Still waiting for a timeout... I can report back, even though it will be my last post (at least directly to your email).



Upgrade can be an option soon.. I also saw xen 3.1.2 was out, so I may upgrade everything at once in a while if the problem persist and no solution is found.

The switches doesn't have anything in the log that could indicate any issue with jumbo frames, or anything else for that matter.

These timeouts are longer than 120 seconds, and the session is dropped in that case.

You could increase the timeout in /etc/iscsi/iscsid.conf (node.session.timeo.replacement_timeout) to a much greater value - in most cases it's a good idea (not only a workaround for your problem until you find a solution, but often helpful if you want to upgrade the iSCSI target, replace cabling, switches etc.).

Anyway, the topic is not very Xen-related and should be directed to a iSCSI-specific list (or e-open support, maybe).

... right, as said above.

Thanks a lot for the insights, very helpful.


Best,

fred


_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users