I am wondering if there are any known issues in running Xen and Xen clients (Linux and/or Windoze) on a server configured with either Linux software RAID, or Fake RAID (which is the same thing). Any help or links? Thanks in advance. David Stockwell _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
David Stockwell wrote:> I am wondering if there are any known issues in running Xen and Xen > clients (Linux and/or Windoze) on a server configured with either Linux > software RAID, or Fake RAID (which is the same thing). >I have some Xen servers running RH5 Xen using mdadm raid 10 on Dom0 with several RH5 domU and feel happy with it. Vu _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Hello, you can look at recent "Xen Disk I/O performance" discussion. On my servers it seems that software RAID works better with Xen than with some hardware RAID :S Olivier David Stockwell a écrit :> I am wondering if there are any known issues in running Xen and Xen > clients (Linux and/or Windoze) on a server configured with either > Linux software RAID, or Fake RAID (which is the same thing). > > Any help or links? > > Thanks in advance. > > David Stockwell > > _______________________________________________ > 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
On Fri, Feb 27, 2009 at 9:51 AM, David Stockwell <dstockwell@frequency-one.com> wrote:> either Linux software > RAID, or Fake RAID (which is the same thing).nope, they''re not the same. FakeRAID is the name given to cards advertised as RAID cards, but in fact are only multiport controllers, and hidden in the drivers is a software RAID. the difference is that with FakeRAID you''re stuck with a proprietary nonmaintained RAID. if you lose the card, you lose the RAID and all data; while Linux software RAID is usable no matter how you connect the drives. even if you lose your only 24-port SATA controller, you could get 6 mainboards, plug 4 drives on each, share each disk via GNBD, access all 24 from another host.... and you''ll see your RAID and all data. -- Javier _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Hello Javier, ----- Original Message ----- From: "Javier Guerra" <javier@guerrag.com>> On Fri, Feb 27, 2009 at 9:51 AM, David Stockwell > <dstockwell@frequency-one.com> wrote: >> either Linux software >> RAID, or Fake RAID (which is the same thing). > > nope, they''re not the same. > > FakeRAID is the name given to cards advertised as RAID cards, but in > fact are only multiport controllers, and hidden in the drivers is a > software RAID. > > the difference is that with FakeRAID you''re stuck with a proprietary > nonmaintained RAID. if you lose the card, you lose the RAID and all > data; while Linux software RAID is usable no matter how you connect > the drives. > > even if you lose your only 24-port SATA controller, you could get 6 > mainboards, plug 4 drives on each, share each disk via GNBD, access > all 24 from another host.... and you''ll see your RAID and all data. > > -- > JavierThanks for the clarification; I knew the controller would be an issue with SCSI RAID (long sad experience), but did not realize that the same issue exists with FakeRAID. Sure am glad I configured all of my drives (only 4 at the moment) as independent AHCI drives (not RAID). The learning journey continues... DS _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Thank you, Vu... I was planning to use my four-plex of 250 GB disks as a RAID-10 (mirrored and striped, or is it the other way around?) array. I was also under the impression that the MoBo was supporting True RAID (silly me...now I know). In any event, I dug around and found a "recipe" at http://linux-raid.osdl.org/index.php/SATA_RAID_Boot_Recipe for setting up a mirror for the boot drive. In also was set up under Mandriva (although I may move to Fedora at some point), so it seems directly applicable. If you have a moment and can share any additional "gotcha"s or advice, I''d appreciate it. Otherwise, thanks for your help and your response. David Stockwell Frequency One Houston, Texas ----- Original Message ----- From: "vu pham" <vu@sivell.com> To: "David Stockwell" <dstockwell@frequency-one.com> Cc: <xen-users@lists.xensource.com> Sent: Friday, February 27, 2009 8:58 AM Subject: Re: [Xen-users] Xen clients and RAID> David Stockwell wrote: >> I am wondering if there are any known issues in running Xen and Xen >> clients (Linux and/or Windoze) on a server configured with either >> Linux software RAID, or Fake RAID (which is the same thing). >> > > I have some Xen servers running RH5 Xen using mdadm raid 10 on Dom0 > with several RH5 domU and feel happy with it. > > > Vu >_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Friday 27 February 2009 14:51:40 David Stockwell wrote:> I am wondering if there are any known issues in running Xen and Xen > clients (Linux and/or Windoze) on a server configured with either Linux > software RAID, or Fake RAID (which is the same thing).Windows guests on phy: on LVM don''t work with software raid 10, tap:aio: on LVM works fine though, as does file:. -- Mike Williams _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users