Hi, I''m new on xen with only a very little experience :( I have setup xen with "Citrix Xen Server 6.0" using one hard disk with only 80 GB. Everything is running fine so far. Now I have added two 1TB SATA disks. Since Xen uses LVM it should be possible to use these 2 disks as lvm stripe for performace reasons. But how to create local storage on these disks? I am looking around but I can not find any samples to build al lvm stripe with ''xe sr-create''. All samples are using just 1 device. How to create local storage using a lvm stipe ? Henning
Henning Ryll wrote:>I have setup xen with "Citrix Xen Server 6.0" using one hard disk with only 80 >GB. Everything is running fine so far. > >Now I have added two 1TB SATA disks. > >Since Xen uses LVM it should be possible to use these 2 disks as lvm stripe >for performace reasons. >But how to create local storage on these disks? > >I am looking around but I can not find any samples to build al lvm stripe with >''xe sr-create''. All samples are using just 1 device. > >How to create local storage using a lvm stipe ?You use the LVM commands to do it - this is absolutely and completely nothing to do with Xen. When you have created the LVM stripe (volume group ?) you can create logical volumes (LVs) within it - either using LVM commands, or any management tool that might handle it for you. Just bear in mind that striping two disks together doubles the risk of failure casing data loss - you now have two disks, and failure of either of them will render the whole set unusable. -- Simon Hobson Visit http://www.magpiesnestpublishing.co.uk/ for books by acclaimed author Gladys Hobson. Novels - poetry - short stories - ideal as Christmas stocking fillers. Some available as e-books.
Am Dienstag 17 April 2012, 18:56:14 schrieb Simon Hobson:> Henning Ryll wrote: > >I have setup xen with "Citrix Xen Server 6.0" using one hard disk with > >only 80 GB. Everything is running fine so far. > > > >Now I have added two 1TB SATA disks. > > > >Since Xen uses LVM it should be possible to use these 2 disks as lvm > >stripe for performace reasons. > >But how to create local storage on these disks? > > > >I am looking around but I can not find any samples to build al lvm stripe > >with ''xe sr-create''. All samples are using just 1 device. > > > >How to create local storage using a lvm stipe ? > > You use the LVM commands to do it - this is absolutely and completely > nothing to do with Xen. When you have created the LVM stripe (volume > group ?) you can create logical volumes (LVs) within it - either > using LVM commands, or any management tool that might handle it for > you. > > Just bear in mind that striping two disks together doubles the risk > of failure casing data loss - you now have two disks, and failure of > either of them will render the whole set unusable.Ok. I know that striping will double the risk of failure. So I have to make sure to have usable backup''s. I have done these steps with LVM now. 1. created 2 physical volumes (i.e. pv_c, pv_d) with pvcreate 2. created a volume group (i.e. vg_c_and_d) with both PV''s 3. created al logical volume (i.e. lv_stripe) on top of the VG But how''s the correct syntax of ''xe sr-create'' now? xe sr-create content-type="local SR" type=lvm device- config:device=/dev/vg_c_and_d/lv_stripe shared=true name-label="Local SR" Doing this I get a second volume group vg_xen..... ! I''m still confused. _______________________________________________ Xen-users mailing list Xen-users@lists.xen.org http://lists.xen.org/xen-users
Hello. I agree with Simon, this has nothing to do with Xen or xe. El 17/04/12 09:57, Henning Ryll escribió:> I am looking around but I can not find any samples to build al lvm stripe with > ''xe sr-create''. All samples are using just 1 device. > > How to create local storage using a lvm stipe ?Check LVM documentation. Essentially, that you probably want is to add the new disk, as a "physical volume" the your main "volume group". This will not give you a block level stripe, instead it will concatenate both storage spaces. In order to get a block level stripe (or any other RAID technology), the common approach is to make LVM to reside over a RAID device instead of a physical disk. It might be hardware RAID, or software md device. -- Alexandre Kouznetsov
On Tue, 04/17/2012 10:57 AM, Henning Ryll <henning@die-rylls.de> wrote:> Hi, > > I''m new on xen with only a very little experience :( > > I have setup xen with "Citrix Xen Server 6.0" using one hard disk with only 80 > GB. Everything is running fine so far. > > Now I have added two 1TB SATA disks. > > Since Xen uses LVM it should be possible to use these 2 disks as lvm stripe > for performace reasons. > But how to create local storage on these disks? >This won''t be possible unless you modify the XAPI code to change how the logical volumes are created. You could of course create everything manually then go back and introduce the SR and the VBDs, but that is a lot of work.
On Tue, 2012-04-17 at 15:57 +0100, Henning Ryll wrote:> Hi, > > I''m new on xen with only a very little experience :( > > I have setup xen with "Citrix Xen Server 6.0" using one hard disk with only 80 > GB. Everything is running fine so far. > > Now I have added two 1TB SATA disks. > > Since Xen uses LVM it should be possible to use these 2 disks as lvm stripe > for performace reasons. > But how to create local storage on these disks? > > I am looking around but I can not find any samples to build al lvm stripe with > ''xe sr-create''. All samples are using just 1 device. > > How to create local storage using a lvm stipe ?If you are running XenServer then you should contact XenServer support or use the XenServer forums on http://community.citrix.com/ so that they can advise you on how to meet your requirements while still remaining within the support envelope. Ian.