From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Hook Subject: persistent or "steady-state" style disks Date: Thu, 16 Feb 2012 12:09:04 -0800 Message-ID: Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============3057443695391217239==" Return-path: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org --===============3057443695391217239== Content-Type: multipart/alternative; boundary=0016e6de002463b18e04b91a66f7 --0016e6de002463b18e04b91a66f7 Content-Type: text/plain; charset=ISO-8859-1 Hi, I have a requirement (and a limited timeframe) to make a Windows 7 VM domain roll back to a fixed state on restart, shutdown etc. Something like a Kiosk Mode. I think this is a very needed part of the core of xen and this functionality does not appear to be part of xen already. So I've been trying various ways to make this work. Has anyone already implemented something like this successfully before? What I've been experimenting unsuccessfully with currently is the following: 1) Add hooks into the blktap2 code to roll back a VHD (currently based on the name ending in -persist.vhd). However, it's not working out as it should. 2) Second attempt was to write an external script and call it periodically. The idea was to call vhd-snapshot on the parent disk to a new disk (temp name). Then do an atomic rename on existing vhd and unlink the old vhd. When it restarts you would think it would open up the new snapshot. Unfortunately, a reboot seems to detect that the file is different and so it's not re-started as desired but instead the domain is shutdown. I don't like either of the above methods. They are hacks in my opinion but I'm not currently familiar enough with xen internals. Can someone propose a method and/or suggest where I could hook into the xen tools to implement it? Regards, Matthew --0016e6de002463b18e04b91a66f7 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Hi,

I have a requirement (and a limited timeframe) to ma= ke a Windows 7 VM domain roll back to a fixed state on restart, shutdown et= c.
Something like a Kiosk Mode. =A0I think this is a very needed = part of the core of xen and this functionality does=A0
not appear to be part of xen already. =A0So I've been trying vario= us ways=A0to make this work.

Has anyone already im= plemented something like this successfully before?

What I've been experimenting unsuccessfully with currently is the follo= wing:

1) Add hooks into the blktap2 code to roll b= ack a VHD (currently based on the name ending in -persist.vhd). =A0
However, it's not working out as it should.

2) Second attempt was to write an external script and call it periodical= ly.
The idea was to call vhd-snapshot on the parent disk to a new= disk (temp name). =A0Then do an atomic rename on existing vhd
and unlink the old vhd. =A0When it restarts you would think it would o= pen up the new snapshot. =A0Unfortunately, a reboot seems to
dete= ct that the file is different and so it's not re-started as desired but= instead the domain is shutdown.

I don't like either of the above methods. =A0They a= re hacks in my opinion but I'm not currently familiar enough with xen i= nternals. =A0
Can=A0someone propose a method and/or suggest where= I could hook into the xen tools to implement it?

Regards,
Matthew
--0016e6de002463b18e04b91a66f7-- --===============3057443695391217239== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel --===============3057443695391217239==--