Hello, I wonder if we can use RAID (hard) under LVM for Xen domU. What kind of RAID is recommanded ? I was thinking about the following configuration: - RAID 1 (two 70 GB disks) for the dom0 - RAID 5 (three 285 GB disks) for domU on LVM partitions Any idea ? Regards, Thomas _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Hi Thomas, On Fri, Feb 08, 2008 at 11:54:31AM +0100, Thomas Bellembois wrote:> I wonder if we can use RAID (hard) under LVM for Xen domU.Yes.> What kind of RAID is recommanded ?The same kind you would use in a normal server. i.e. spec it for your usage. Personally I run out of IO before CPU or RAM so I try to use the most performant RAID level - RAID-10. If your needs are different then you may choose differently. Xen will work on whatever. Cheers, Andy _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Hi Andy, Thanks a lot for your answer. Regards, Thomas Andy Smith wrote:> Hi Thomas, > > On Fri, Feb 08, 2008 at 11:54:31AM +0100, Thomas Bellembois wrote: > >> I wonder if we can use RAID (hard) under LVM for Xen domU. >> > > Yes. > > >> What kind of RAID is recommanded ? >> > > The same kind you would use in a normal server. i.e. spec it for > your usage. > > Personally I run out of IO before CPU or RAM so I try to use the > most performant RAID level - RAID-10. If your needs are different > then you may choose differently. Xen will work on whatever. > > Cheers, > Andy > > ------------------------------------------------------------------------ > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Thomas Bellembois wrote:> Hello, > > I wonder if we can use RAID (hard) under LVM for Xen domU. > What kind of RAID is recommanded ? > > I was thinking about the following configuration: > - RAID 1 (two 70 GB disks) for the dom0 > - RAID 5 (three 285 GB disks) for domU on LVM partitions > > Any idea ? > > Regards, > > Thomas >Yes. *NEVER* do RAID *inside* a DomU. Every cycle in DomU for disk management has to be filtered down to the hypervisor anyway, and software RAID is thus a complete waste in DomU. Leave the disk management to the Dom0, because all you''re doing is adding a layer of complexity to the DomU interactions with hardware that buy you *nothing* unless your software itself is capable of corrupting the internal filesystem and you want to poke around with it. But usually there''s no point. Now, if you mean setting up 3 disks on Dom0 using RAID5, great. Better yet, use a cheap hardware controller and keep the RAID processing off of Dom0, too. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users