Re: Fwd: Re: Raw Disk still preferred for 11.5? - File system type for SDS

On Wednesday 08 October 2008 19:17:32 you wrote: > The sysadmin corrected me - OCFS2 - I dont know if that makes much > difference or not.. > > laurie > > Laurie Gustin" <lgustin@utah.gov> 10/08/08 11:03 AM >>> > > Thanks so much for all the feedback, I have learned a great deal. I think > we will go with a cooked system. I think it will be better > administratively, since they wont give me root access to the new servers > and it will be a chance to try something new and test the performance. > > Now I am getting questions from the sys admins about file system type. We > are going to implement SDS servers that will access the same disk on a SAN. > As of today.. the plan is to use OCFS file system. (rather than Risser or > ext3). Any comments on this? > > Also - I have been reading the manuals, and blogs, and whitepapers, etc., > about seeting up SDS servers and it really doesnt talk much about how the > shared disk is accesed/referenced on the SDS servers. I have always > figured the sys admins should know how to do this... but it is causing a > lot of questions. Is there somewhere I can send these guys to give them > the info they need to set up the shared disk part of it? If a SAN is available to your servers think about access the disk devices directly. Primary and SDS servers can share the same SAN provided disk partitions. To my mind this is much easier to configure and performs better than a cluster filesystem. With IDS 11.50.UC2 the Linux block devices will be opened with O_DIRECT automatically which switch of buffering. So there is no need to create character (raw) devices. Also in a SAN I would recommend to use persistent device paths provided by dynamic device management (udev) in in /dev/disk/by-path or /dev/disk/by-uuid . BTW which type of SAN do you use? Andreas > > Thanks a bunch!!! > > Laurie > > > > Laurie Gustin > IT Programmer Analyst > Department of Public Safety > lgustin@utah.gov > 801-965-4410 -- Andreas Breitfeld; Informix Development Munich IBM Deutschland Research & Development GmbH; Vorsitzender des Aufsichtsrats: Martin Jetter; Geschaeftsfuehrung: Erich Baier; Sitz der Gesellschaft: Boeblingen; Registergericht: Amtsgericht Stuttgart, HRB 243294