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-devel

Re: [Xen-devel] Cloning(making copies) of VMs

To: sowmya dayanand <sowmyad@xxxxxxxxx>
Subject: Re: [Xen-devel] Cloning(making copies) of VMs
From: Jacob Gorm Hansen <jacobg@xxxxxxx>
Date: Tue, 8 Nov 2005 08:34:08 +0100
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx
Delivery-date: Tue, 08 Nov 2005 07:34:59 +0000
Domainkey-signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=QareD8doxp25HNJ8LO7cjjCnbJydbl/K+PF5UTxkReFf0YxRY3WKf1dBmY2xrvcwDJLmVYN2iEM3vxfjOCcYdwWXhiMirXAfiV3vTGIcNniwLYGPT6n1yszPgBnK/ORk+xC+sYxXazW/HoPAlgb0lVuZPVJLDlynn7tUQCXIJGQ=
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <83c5685b0511072225u40ba05c9t121ea92c942286a1@xxxxxxxxxxxxxx>
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
References: <83c5685b0511072225u40ba05c9t121ea92c942286a1@xxxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
On 11/8/05, sowmya dayanand <sowmyad@xxxxxxxxx> wrote:

> (VM1 is a virtual machine, with ip addr 10.10.10.1, and we want to clone it
> as VM2, with ip addr 10.10.10.2) both running on the same physical machine.
>
> 1) Save VM1 as VM1_save (using xm save)
> 2) copy VM1_save to VM2_save
> 3) Change the vmid and the IP address info in the saved file to that of VM2
> (Any other information to be changed ?)
> 4) Restore VM1_save and VM2_save (using xm restore)

The problem is that while you are probably sucessful in telling the
host environment (xen + linux in domain0) that your cloned VM has IP
10.10.10.2, the Linux inside VM2 does not know that it is supposed to
answer the new IP rather than 10.10.10.1, and will just silently drop
all traffic on 10.10.10.2. It would probably be quite simple (and
useful, see the Potemkin paper for instance) to have your domain
answer any incoming IP, or to rewrite all ingoing and outgoing packets
with a generic address, but you will need to hack either your guest
Linux or the networking scripts in dom0 to make that happen.

Best,
Jacob

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