[Gluster-devel] Setup recommendations ?

[Anton Khalikov]

Hello everyone

We have a few servers with xen based vps on them. At the moment every
server works on it's own and no live migration etc is made.

We are looking for a solution where we could do fast live or easy
offline migration of domUs between servers and glusterfs seems to be one
of the best options available.

Our problem is that we already have 6 servers with running domUs and we
need to move to the new scheme with minimal downtime and minimal
additional investments into hardware. Currently every server has 2
SATA-II disks which are plugged into RAID-1 and every domU gets disk
space from LVM.

The idea is to have exactly 2 copies of every domU partition (they will
be just plain files with ext3 system inside) so we would have something
like distributed RAID-1 between glusterfs members. 

As I understand, we can switch disks to RAID-0 (it would give us twice
more hdd space and additional disk speed because of stripping) and use
glusterfs' AFR translators to RAID-1 between servers. So we need to join
servers into pairs and every pair should behave like RAID1 and this way
we get 2 copies of every domU partitions and at any time we
theoretically can switch one server down without stopping the service.
Of course these server pairs need to be joined into a common namespace
using Unify translator. Interconnect will be GigE (separate interfaces).

Could anyone tell me his opinion about such solution or maybe suggest
anything else. Recommendations about required translators and best usage
practices would be also appreciated.

--
Best regards
Anton Khalikov