I am about to get a few extra servers and hopefully a NAS for here at work. Currently all of our VM''s are on one host that has a raid6 with approx 12TB usable. The way I would like to set things up is to where the disk images (we use lvm partitions for guest disks) sit on the NAS and use something like DRBD or similar to allow live failover. We are using Xen 4.0 on a Centos 5.5 Dom0 if that matters. So how would you recommend setting up the system to allow shared storage (NAS) with live failover using lv disks? I wouldn''t need to failover every guest, just the primary ones like mail, web, ldap. Thanks for any input. -- Donny B. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Also let me explain my planned roadmap. Instead of buying huge Dell T710 style servers with cpu, ram, and disks, from this point on I would like to just have a NAS or two and then have some small 1U server that have the cpu and ram to run the guests on. That is the main reason for the live failover. -- Donny B. On Tuesday, August 10, 2010 01:43 PM CDT, Donny Brooks <dbrooks@mdah.state.ms.us> wrote:> I am about to get a few extra servers and hopefully a NAS for here at work. Currently all of our VM''s are on one host that has a raid6 with approx 12TB usable. The way I would like to set things up is to where the disk images (we use lvm partitions for guest disks) sit on the NAS and use something like DRBD or similar to allow live failover. We are using Xen 4.0 on a Centos 5.5 Dom0 if that matters. > > So how would you recommend setting up the system to allow shared storage (NAS) with live failover using lv disks? I wouldn''t need to failover every guest, just the primary ones like mail, web, ldap. Thanks for any input. > > -- > > Donny B. > > _______________________________________________ > 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 Tuesday 10 August 2010 20:53:07 Donny Brooks wrote:> Also let me explain my planned roadmap. Instead of buying huge Dell T710 > style servers with cpu, ram, and disks, from this point on I would like to > just have a NAS or two and then have some small 1U server that have the > cpu and ram to run the guests on. That is the main reason for the live > failover. > > > I am about to get a few extra servers and hopefully a NAS for here at > > work. Currently all of our VM''s are on one host that has a raid6 with > > approx 12TB usable. The way I would like to set things up is to where the > > disk images (we use lvm partitions for guest disks) sit on the NAS and > > use something like DRBD or similar to allow live failover. We are using > > Xen 4.0 on a Centos 5.5 Dom0 if that matters. > > > > So how would you recommend setting up the system to allow shared storage > > (NAS) with live failover using lv disks? I wouldn''t need to failover > > every guest, just the primary ones like mail, web, ldap. Thanks for any > > input. > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users >For DRBD you need a something to do the DRBD and you would need two NAS boxes. How about using your NAS as an iSCSI box? _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Well the disk box we are looking at is the Dell MD3000i so iscsi is an option. Does xen handle that better than other protocols? I am kinda new to the whole shared network disk stuff. -- Donny B. On Tuesday, August 10, 2010 03:04 PM CDT, Bart Coninckx <bart.coninckx@telenet.be> wrote:> On Tuesday 10 August 2010 20:53:07 Donny Brooks wrote: > > Also let me explain my planned roadmap. Instead of buying huge Dell T710 > > style servers with cpu, ram, and disks, from this point on I would like to > > just have a NAS or two and then have some small 1U server that have the > > cpu and ram to run the guests on. That is the main reason for the live > > failover. > > > > > I am about to get a few extra servers and hopefully a NAS for here at > > > work. Currently all of our VM''s are on one host that has a raid6 with > > > approx 12TB usable. The way I would like to set things up is to where the > > > disk images (we use lvm partitions for guest disks) sit on the NAS and > > > use something like DRBD or similar to allow live failover. We are using > > > Xen 4.0 on a Centos 5.5 Dom0 if that matters. > > > > > > So how would you recommend setting up the system to allow shared storage > > > (NAS) with live failover using lv disks? I wouldn''t need to failover > > > every guest, just the primary ones like mail, web, ldap. Thanks for any > > > input. > > > > _______________________________________________ > > Xen-users mailing list > > Xen-users@lists.xensource.com > > http://lists.xensource.com/xen-users > > > > For DRBD you need a something to do the DRBD and you would need two NAS boxes. > How about using your NAS as an iSCSI box? > > _______________________________________________ > 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
iSCSI will give you very good performance. Much better than NFS, for instance. MD3000i''s are a bit of a pain though, multipathing these units using dm-multipath doesn''t work very well in my experience. The latest versions of RHEL do have improved support for MD3000i''s though, very much depends on the Dom0 linux distribution you''re using? Personally, in this sort of setup I''ve always gone for a cLVM based approach. Means you don''t have to faff about with clustered filesystems and should be as scalable as you could ever need! Last role I was in I had 15 MD3000i''s and 6 R900''s in this configuration supporting ~300VM''s and it was very fast and stable. As for HA failover, I''ve used heartbeat for this in the past with good results but with Xen 4.0 there are various options I''m not experienced with. RDMA looks great, for instance. Not sure how mature it is yet though. On Tue, Aug 10, 2010 at 9:44 PM, Donny Brooks <dbrooks@mdah.state.ms.us> wrote:> Well the disk box we are looking at is the Dell MD3000i so iscsi is an option. Does xen handle that better than other protocols? I am kinda new to the whole shared network disk stuff. > > > -- > > Donny B. > > On Tuesday, August 10, 2010 03:04 PM CDT, Bart Coninckx <bart.coninckx@telenet.be> wrote: > >> On Tuesday 10 August 2010 20:53:07 Donny Brooks wrote: >> > Also let me explain my planned roadmap. Instead of buying huge Dell T710 >> > style servers with cpu, ram, and disks, from this point on I would like to >> > just have a NAS or two and then have some small 1U server that have the >> > cpu and ram to run the guests on. That is the main reason for the live >> > failover. >> > >> > > I am about to get a few extra servers and hopefully a NAS for here at >> > > work. Currently all of our VM''s are on one host that has a raid6 with >> > > approx 12TB usable. The way I would like to set things up is to where the >> > > disk images (we use lvm partitions for guest disks) sit on the NAS and >> > > use something like DRBD or similar to allow live failover. We are using >> > > Xen 4.0 on a Centos 5.5 Dom0 if that matters. >> > > >> > > So how would you recommend setting up the system to allow shared storage >> > > (NAS) with live failover using lv disks? I wouldn''t need to failover >> > > every guest, just the primary ones like mail, web, ldap. Thanks for any >> > > input. >> > >> > _______________________________________________ >> > Xen-users mailing list >> > Xen-users@lists.xensource.com >> > http://lists.xensource.com/xen-users >> > >> >> For DRBD you need a something to do the DRBD and you would need two NAS boxes. >> How about using your NAS as an iSCSI box? >> >> _______________________________________________ >> 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 >_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Hi, xcp handles iscsi fine, if you have the time Id suggest you investigate opensolaris as an alternative to the MD3000i. Im using osol with R610s and MD1000 for storage, working great, took some time to iron out all the wrinkles though. Best regards, Rune Den 10.08.2010 22:44, skrev Donny Brooks:> Well the disk box we are looking at is the Dell MD3000i so iscsi is an option. Does xen handle that better than other protocols? I am kinda new to the whole shared network disk stuff. > >_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Tuesday 10 August 2010 22:44:43 Donny Brooks wrote:> Well the disk box we are looking at is the Dell MD3000i so iscsi is an > option. Does xen handle that better than other protocols? I am kinda new > to the whole shared network disk stuff. > > > On Tuesday 10 August 2010 20:53:07 Donny Brooks wrote: > > > Also let me explain my planned roadmap. Instead of buying huge Dell > > > T710 style servers with cpu, ram, and disks, from this point on I would > > > like to just have a NAS or two and then have some small 1U server that > > > have the cpu and ram to run the guests on. That is the main reason for > > > the live failover. > > > > > > > I am about to get a few extra servers and hopefully a NAS for here at > > > > work. Currently all of our VM''s are on one host that has a raid6 with > > > > approx 12TB usable. The way I would like to set things up is to where > > > > the disk images (we use lvm partitions for guest disks) sit on the > > > > NAS and use something like DRBD or similar to allow live failover. We > > > > are using Xen 4.0 on a Centos 5.5 Dom0 if that matters. > > > > > > > > So how would you recommend setting up the system to allow shared > > > > storage (NAS) with live failover using lv disks? I wouldn''t need to > > > > failover every guest, just the primary ones like mail, web, ldap. > > > > Thanks for any input. > > > > > > _______________________________________________ > > > Xen-users mailing list > > > Xen-users@lists.xensource.com > > > http://lists.xensource.com/xen-users > > > > For DRBD you need a something to do the DRBD and you would need two NAS > > boxes. How about using your NAS as an iSCSI box? > >It''s one of the more standard protocols to do that, but it''s not the only one. But with the MD3000i it makes the most sense I think. Mind you, your MD3000i will be a SPOF. Look at my other reply regarding a HA solution. B. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users