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] Watchdog support in XEN?

To: "Eric S. Johansson" <esj@xxxxxxxxxx>
Subject: Re: [Xen-users] Watchdog support in XEN?
From: Mark Williamson <mark.williamson@xxxxxxxxxxxx>
Date: Wed, 27 Jul 2005 20:58:20 +0100
Cc: "Andreas Bach Aaen \(AH/TED\)" <andreas.bach.aaen@xxxxxxxxxxxx>, xen-users@xxxxxxxxxxxxxxxxxxx
Delivery-date: Wed, 27 Jul 2005 19:56:55 +0000
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <42E7DF25.80006@xxxxxxxxxx>
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: <200507262153.54570.andreas.bach.aaen@xxxxxxxxxxxx> <200507262113.22944.mark.williamson@xxxxxxxxxxxx> <42E7DF25.80006@xxxxxxxxxx>
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: KMail/1.7.1
> forgive me if I'm misunderstanding something but it seems to me that one
> would want to use a hardware watchdog on dom0 so if the system should
> well and truly fail, an undeniable reset could be applied to the entire
> system.  But if dom0 is healthy, then yes, a software watchdog in dom0
> paying attention to and deciding when to reset the various domU's should
> be sufficient.

I think you'd ideally want both:
* Hardware watchdog in dom0 in case dom0 or Xen crashes
* Software watchdog for domU is provided by dom0 (which we can guarantee is up 
because of the hardware watchdog) via the store

In the absence of a hardware watchdog, you could also implement a software 
watchdog for dom0 in Xen itself, which is likely to be the most reliable 
piece of code in the system and shouldn't lock up even if dom0 does.

Cheers,
Mark

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

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