Dear All, I have installed Gluster FS v. 1.3.12 on 2 server with Debian 4.05, in AFR with client side replication, explained in this page: http://www.gluster.org/docs/index.php/Setting_up_AFR_on_two_servers_with_client_side_replication Tested to work! :-) Now, my idea: Use a Xen Hypervisor with image disk data for DomU machines on GlusterFS repository In my Gluster FS client machine (based on Centos 5.2), I have create a DomU machine with image file stored in local disk (/var/lib/xen/images/), Called "Debian4" Start and finish installation without problems! Now, I have moved image file from /val/lib/xen/images/ to my GlusterFS directory (/mnt/glusterfs/) O.k., checked that image file, I''m go to modify DomU configuration with new image disk path.... First setting: disk = [ ''file:/mnt/glusterfs/debian40.img,hda1,w'' ] Start DomU, I retry this error: xend.err ''Device 768 (vbd) could not be connected. losetup /dev/loop0 /mnt/glusterfs/debian40.img failed'' Into log explained error is: domid: 22 qemu: the number of cpus is 1 Watching /local/domain/22/logdirty/next-active xs_read(): vncpasswd get error. /vm/353e360e-bcdd-f237-595e-85013704aad7/vncpasswd. char device redirected to /dev/pts/4 qemu_map_cache_init nr_buckets = 10000 shared page at pfn 1ffff buffered io page at pfn 1fffd xs_read(/vm/353e360e-bcdd-f237-595e-85013704aad7/rtc/timeoffset): read error I/O request not ready: 0, ptr: 0, port: 0, data: 0, count: 0, size: 0 Triggered log-dirty buffer switch Second setting: disk = [ ''tap:aio:/mnt/glusterfs/debian40.img,hda1,w'' ] Machine start and stop Into log explained error is: qemu: could not open hard disk image ''aio:/mnt/glusterfs/debian40-dnsldap.img'' Watching /local/domain/21/logdirty/next-active xs_read(): vncpasswd get error. /vm/353e360e-bcdd-f237-595e-85013704aad7/vncpasswd. char device redirected to /dev/pts/4 qemu_map_cache_init nr_buckets = 10000 shared page at pfn 1ffff buffered io page at pfn 1fffd xs_read(/vm/353e360e-bcdd-f237-595e-85013704aad7/rtc/timeoffset): read error I/O request not ready: 0, ptr: 0, port: 0, data: 0, count: 0, size: 0 Triggered log-dirty buffer switch O.k., people have a solution? Many Thanks, Enrico Valsecchi _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Mon, 24 Nov 2008, Enrico Valsecchi wrote:> Dear All, > > I have installed Gluster FS v. 1.3.12 on 2 server with Debian 4.05, > in AFR with client side replication, explained in this page: > http://www.gluster.org/docs/index.php/Setting_up_AFR_on_two_servers_with_client_side_replication > Tested to work! > > :-) > > Now, my idea: > > Use a Xen Hypervisor with image disk data for DomU machines on GlusterFS > repositoryYour going to run into a lot of issues with loop files. Unfortunately Gluster does not support tap:aio, so the only thing left is look with issues. :( I wish so much that this was not the case, but after working on this for about 6 months I ended up going with DRBD. It is much more limited then Gluster, but stable as a rock.><>Nathan Stratton CTO, BlinkMind, Inc. nathan at robotics.net nathan at blinkmind.com http://www.robotics.net http://www.blinkmind.com _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
After some test, I have solved problem to use a SAN based on GlusterFS to store xen images. All work very very fine. Software used: Xen v. 3.2 build under Centos 5.2 X_64 GlusterFS v. 1.3.12 Configure GlusterFS in your favorite mode (AFR, Mirror, Unify, is not a problem) Mount GlusterFS in client environment with DISABLE DIRECTIO: - version 1.3: glusterfs -d disable -f /path-of-volume-spec-file - version 1.4: glusterfs --disable-direct-io-mode -f /path-of-volume-spec-file Now, if Gluster work correctly, you can store Xen Image file into space allowed by GlusterFS You can specify, in domU configuration file, disk type: tap:aio:/GlusterFs-mount-point/domU-image-disk, hda, etc etc etc etc (suggested method) OR file:/GlusterFs-mount-point/domU-image-disk, hda, etc etc etc etc Bye, Enrico> On Mon, 24 Nov 2008, Enrico Valsecchi wrote: > >> Dear All, >> >> I have installed Gluster FS v. 1.3.12 on 2 server with Debian 4.05, >> in AFR with client side replication, explained in this page: >> http://www.gluster.org/docs/index.php/Setting_up_AFR_on_two_servers_with_client_side_replication >> >> Tested to work! >> >> :-) >> >> Now, my idea: >> >> Use a Xen Hypervisor with image disk data for DomU machines on GlusterFS >> repository > > Your going to run into a lot of issues with loop files. Unfortunately > Gluster does not support tap:aio, so the only thing left is look with > issues. :( I wish so much that this was not the case, but after > working on this for about 6 months I ended up going with DRBD. It is > much more limited then Gluster, but stable as a rock. > >> <> > Nathan Stratton CTO, BlinkMind, Inc. > nathan at robotics.net nathan at blinkmind.com > http://www.robotics.net http://www.blinkmind.com > >_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users