Diskless Boot of Windows/iSCSI

OnTap 7 has the ability to create Flex Clones - basically a new volume based on an old one, initially sharing all the same blocks. While Windows is running, the blocks would be changed. If you screwed up, shut down Windows, destroy the Flex Clone volume then create a new one and restart Windows on the new Flex Clone.

In your other scenario, you could SnapRestore a snapshot of a LUN as it is a single file and you can SnapRestore single files - nearly instantaneous recovery

----- Original Message -----

Sent: Wednesday, February 09, 2005 5:35 PM

Subject: RE: Diskless Boot of Windows/iSCSI

No sure if you have gotten additional answers. But you might want to look into writable LUN. It is a LUN based on snapshot and can be changed but at some point you can just throw it away and off goes all the changes. It is pretty quick to create the writable LUN.

This fits 1/2 the model, the key is that the base load never changes..if the end-user changes something that could have messed the encoding process up somehow, a simple reboot would repair it.

To replace the base LUNs, I would have to copy from the snapshot, would take time to copy that file from snapshot space to real space, correct?

Ive got Gig to the tent switch (clean workspace on refuel floor) and 100Mbit from there to the PCs. Performance should be in the OK range. The critical function for these PCs is encoding video, once loaded up network traffic for apps or I/O would be small.

Also looking at some solutions that manage disk images that will always force clients to a base boot image on a reboot, but Id like to keep the technology layer thin, and I already have netapps in the design.

Jeff,

As long as you have the base snapshot you can replace the boot LUNs quickly. You can also replicate this image to all of the field sites so that each are configured identically.

The one major problem is the hardware has to be identical on each PC that will boot from SAN if you want to use the same image. You'll also need an iSCSI HBA. I would make sure that Network connectivity is reliable between the 250's and the PC's.

I believe that the NOW site has instructions on seeting up a diskless system and the requirements to double check.

From: owner-toasters@mathworks.com on behalf of Jeff Mohler
Sent: Sun 2/6/2005 5:19 PM
To: toasters@mathworks.com
Subject: Diskless Boot of Windows/iSCSI

Greets:

Same name, new location..

Im working a storage solution under contract using Netapp F250s in the field using snapmirror to replicate data back to a central F270 from nuclear plant inspection projects all over the world.

I have 8 windows based PCs at each site doing encoding of camera inspections (IVVI), and those write to a file and/or go live over the network to the central location based on the inspection parameters.

My largest source of problems are the encoding PCs which are not in the friendliest of environments on the refueling floor. Im looking for advice on whether I should change these PCs to work as diskless boot stations using ISCSI from the F250 that is at each site.

The ultimate goal would be a situation where on boot the PC is booted to a static state of base configuration, and if the end-user changes anything (within MS Media encoder/etc) they just reboot to get back to a reliable configuration. The end user isnt storing any data in this image, just USING it to create data stored in a volume on the same F250 at the remote site.

Just how diskless can I get, while maintaining an easy to use environment where nobody can screw up the base load image?

My window of downtime is 10mins or less to full recovery.