Hi, Our group would really like to use XenSource to run a very large number of parallel Windows XP VMs, but there are several issues we need to overcome or else we''ll have to use ESX instead. This is pretty high priority so if there is a high-level tech at XenSource who knows how to solve this, we would be really grateful. (1) We want to start-up using a post-boot save of Windows XP and the run a software test envrionment in the VM where any file write to the boot drive (misc, registry etc) is written to a spool/log (similar to a file system journal) so that writes don''t corrupt our common XP image. (2) When we shut down the VM we still need access to the journal so we can do a "diff" on what happened during testing. I know its possible to use some sort of system shim to catch OS writes, but we want to keep OS modification to a minimum. Whether we do this via some sort of shim into an OS callgate we still need to make various read/writes to the common shared image transparent / non-corrupting of the shared image. I know how to do that in Linux. You use variously overlay file systems. How do you do it in Windows. In other words, we have a very nice potential demonstration system for XenEnterprise/XenSource. I''d like to talk to a senior tech about the deep tech issues. As much as I like to talk to Sales people about this, these are *very deep* technical issues. I would appreciate a pointer though if you know the engineer to talk to. Jim Burnes _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Artur Linhart - Linux communication
2007-Jun-20 23:22 UTC
RE: [Xen-users] Hard Problem /w XenSource / XenEnterprise.
Hello, I am no xen or generally linux expert and I do not understand clearly everything You write, but at least some from Your requirements seem for me to be realizable by the DomU installed on the logical volume. Always you want to start Your new VM, You can create a new writable snapshot logical volume of the original logical volume (as far as I kow at least theoretically, it is possible). So You can run a lot of such "snapshot" DomUs which all base on same original data. If You want to modify the original data, You can just start the original DomU, modify the original DomU VM (install new software, etc) and if the original DomU is modified, then shut down this "original" DomU and use the original logical volume - now in consistent new state - again for the start of the "snapshot" DomUs... You can then compare the original logical volume with the modified snapshot volume and so find out which files - or data on the logical volume - have been changed. I think, there are also the tools in Windows which can log the disc/files/registry accesses and modifications, so You can install it by default on the Original DomU and then it will log all Your modifications in every started "snapshot" DomU... But I do not know exactly which tool it is, there are just some monitoring tools for this purpose, look in the internet for them. Of course, You have written You know how to make it in Linux, so maybe this way is not suitable for You - but from Your questions I do not understand exactly why it is not possible to make it in the way I described... Maybe I am wring - like written, I am not an expert.... :-) With regards Archie _____ From: xen-users-bounces@lists.xensource.com [mailto:xen-users-bounces@lists.xensource.com] On Behalf Of Jim Burnes Sent: Tuesday, June 19, 2007 10:29 PM To: xen-users@lists.xensource.com Subject: [Xen-users] Hard Problem /w XenSource / XenEnterprise. Hi, Our group would really like to use XenSource to run a very large number of parallel Windows XP VMs, but there are several issues we need to overcome or else we''ll have to use ESX instead. This is pretty high priority so if there is a high-level tech at XenSource who knows how to solve this, we would be really grateful. (1) We want to start-up using a post-boot save of Windows XP and the run a software test envrionment in the VM where any file write to the boot drive (misc, registry etc) is written to a spool/log (similar to a file system journal) so that writes don''t corrupt our common XP image. (2) When we shut down the VM we still need access to the journal so we can do a "diff" on what happened during testing. I know its possible to use some sort of system shim to catch OS writes, but we want to keep OS modification to a minimum. Whether we do this via some sort of shim into an OS callgate we still need to make various read/writes to the common shared image transparent / non-corrupting of the shared image. I know how to do that in Linux. You use variously overlay file systems. How do you do it in Windows. In other words, we have a very nice potential demonstration system for XenEnterprise/XenSource. I''d like to talk to a senior tech about the deep tech issues. As much as I like to talk to Sales people about this, these are *very deep* technical issues. I would appreciate a pointer though if you know the engineer to talk to. Jim Burnes _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users