On 11/03/13 15:30, Indivar Nair wrote: > The best configuration to go for should be based on your file sizes, > file count and read / write patterns. > But as such you are right, Jerome. > > *In general -* > ----------------- > > The best RAID Configuration would be to create one that aligns with the > 1MB I/O size of Lustre. > > Say you have 1 x MD3200 and 4 x MD1200 expansion arrays. That would give > you 60 Disks. > So the best option here would be to create 6 RAID6 Arrays of 10 Disks each. > In this case, you would end up having - 6 RAID6 Arrays = 6 LUNs = 6 OSTs. > > In each of the 10 Disk RAID6 Array, you would get 8 Data Disks and 2 > Parity Disks. > Now if you divide 1MB (I/O Size) by 8 Data Disks, it gives you - *128KB* > - the segment / chunk size you should go for. > This config will align the I/O reads / writes, giving you the best > performance possible with the disk set. > > Divide the 6 OSTs among 2 OSS Nodes, and configure the nodes to act as > failover to each other. > Just ensure that each node has enough RAM to support 6 OSTs, in case one > of them fails. >
http://content.dell.com/uk/en/enterprise/d/hpcc/cambridge-hpc-solution-centre Has links to a couple of white papers with Dell MD3200s and MD1200s in a failover configuration. They use 2*(MD3200 + 4*MD1200 +server) to give a failover solution - which looks like exactly the setup you describe. Chris > Hope this helps. > > Regards, > > > Indivar Nair > > > On Mon, Mar 11, 2013 at 6:31 PM, Jerome, Ron <[email protected] > <mailto:[email protected]>> wrote: > > I am currently having a debate about the best way to carve up Dell > MD3200's to be used as OST's in a Lustre file system and I invite > this community to weigh in... > > I am of the opinion that it should be setup as multiple raid groups > each having a single LUN, with each raid group representing an OST, > while my colleague feels that it should be setup as a single raid > group across the whole array with multiple LUNS, with each LUN > representing an OST. > > Does anyone in this group have an opinion (one way or another)? > > Regards, > > Ron Jerome > _______________________________________________ > Lustre-discuss mailing list > [email protected] <mailto:[email protected]> > http://lists.lustre.org/mailman/listinfo/lustre-discuss > > > > > _______________________________________________ > Lustre-discuss mailing list > [email protected] > http://lists.lustre.org/mailman/listinfo/lustre-discuss _______________________________________________ Lustre-discuss mailing list [email protected] http://lists.lustre.org/mailman/listinfo/lustre-discuss
