On 03/08/2013 02:17 PM, Mihály Árva-Tóth wrote:
Hello, We're planning 3 hosts, 12 HDDs in each host. Which is the better? If we set up 1 OSD - 1 HDD structure or create hardware RAID-6 all of 12 HDDs and only one OSD uses the whole disk space in one host?
I'd saw 12 "RAW" disks, so 12 OSDs. It will consume a bit more memory and CPU, but since Ceph does the replication there is no need for HW-RAID, it's just wasting space.
But still, 3 hosts with 12 HDDs each is not what I'd recommend. If you loose one host 33% of your cluster goes down and the recovery process will consume a lot of performance.
Better go with 6 hosts with each 6 disks or even more hosts with each less disks.
The more hosts you have the lower the impact is of loosing one.
Thank you, Mike _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
-- Wido den Hollander 42on B.V. Phone: +31 (0)20 700 9902 Skype: contact42on _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com