On 03/03/16 21:57, [email protected] wrote:
I have a client that wants to build small remote sites to sync back to an ESS cluster they purchased. These remote sites are generally <15-20TB. If I build a three node cluster with just internal drives can this work if the drives aren’t shared amongst the cluster without FPO or GNR(since it’s not ESS)? Is it better to have a SAN sharing disks with the three nodes? Assuming all are NSD servers (or two at least). Seems like most of the implementations I’m seeing use shared disks so local drives only would be an odd architecture right? What do I give up by not having shared disks seen by other NSD servers?
Unless you are doing data and metadata replication on the remote sites then any one server going down is not good at all. To be honest I have only ever seen that sort of setup done once. It was part of a high availability web server system. The idea was GPFS provided the shared storage between the nodes by replicating everything.
Suffice as to say keeping things polite "don't do that". In reality the swear words coming from the admin trying to get GPFS fixed when disks failed where a lot more colourful. In the end the system was abandoned and migrated to ESX as it was back then. Mind you that was in the days of GPFS 2.3 so it *might* be better now; are you feeling lucky?
However a SAS attached Dell MD3 (it's LSI/Netgear Engenio storage so basically the same as a DS3000/4000/5000) is frankly so cheap that it's just not worth going down that route if you ask me. I would do a two server cluster with a tie breaker disk on the MD3 to avoid any split brain issues, and use the saving on the third server to buy the MD3 and SAS cards.
JAB. -- Jonathan A. Buzzard Email: jonathan (at) buzzard.me.uk Fife, United Kingdom. _______________________________________________ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
