On Mon, 07 Apr 2014 19:13:32 +0200 Michal Humpula wrote: > Hi everybody, > > I'm looking for any hints on how to choose the hardware for small ceph > cluster, roughly size of a 10-20TB. Primary purpose of this cluster is > to have a centralized (from the client point of view), but fault > tolerant storage for images served by webserver (i.e. mostly read IO). > > I was thinking to buy a microcloud supermicro, two of these: > > http://www.supermicro.com/products/system/3U/5038/SYS-5038ML-H8TRF.cfm > You will pay through your nose for those Intel CPUs which are total overkill for a single disk OSD. The same is true for memory, etc. a single disk OSD with SSD journal doesn't make much sense unless you have money to burn and very write intensive loads. Also keep in mind that you're limited to GbE with that default setup.
> Single node has two disks, so I would put in one SSD on system an OSD > journal and one 3TB SATA disk for data. > > My concern is, that this goes against recommendations mentioned in > http://ceph.com/docs/master/start/hardware-recommendations/ > i.e. putting the journal and the system on the same disk, but the system > IO should be minimal in this setup, if I'm not mistaken. > > I would welcome any recommendation of how to best pull this off with the > Ceph. > OSD logs and OS chatter is minimal, you would be fine with this, provided you're putting the MONs on other machines. However even if we consider the 2 chassis as completely independent failure domains, you will get 60TB out of this in raw storage, meaning 20TB with a replication of 3 which is what you want unless your data is worthless to you. Something cheaper would be along the lines of 3 2U cases with 12 disks each, use up to 4 SSDs (good ones) for OS and logs as you're read bound and 8 OSD disks, with an AMD mobo for a total of 24TB Ceph storage. And if money is tight, start with 4 3TB disks and add more OSD HDDs later. Regards, Christian > Cheers > Michal > _______________________________________________ > ceph-users mailing list > [email protected] > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > -- Christian Balzer Network/Systems Engineer [email protected] Global OnLine Japan/Fusion Communications http://www.gol.com/ _______________________________________________ ceph-users mailing list [email protected] http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
