More comments inline.. Tharindu Rukshan Bamunuarachchi wrote: > hi Atul, > > few points ... > > 1. we have migrated to SuSE11 from Solaris due to various techno/political > reasons. > 2. I will keep OSS1/MDS2 & OSS2/MDS1 etc. as you have instructed. > > One last thing ... > > so, I can configure lustre in a way that ... > when either node_A or node_B is down (e.g. power failure) , clients can > still access file system without data lost :-) > Yes you can, Lustre clients will see brief hang till failover is done and will resume their operations (assuming that storage need not undergo fsck).
Cheers, -Atul > thankx a lot for quick response ... > > __ > tharindu > > > > > Hi Tharindu, > > Some comment inline... > > Tharindu Rukshan Bamunuarachchi wrote: > >> we used sun cluster for shared storage access. we are going to migrate >> to lustre. >> >> we have two nodes connected to single 2540 disk array. >> >> > Sun cluster runs on Solaris whereas Lustre is purely Linux. I hope you > know that. > >> >> >> we are going to keep OSS1/MDS in node A and OSS2/MDS in node B. >> >> Please find attached diagram. >> >> > > It is generally not a good idea to co-locate OSS and MDS on same node. > It kind of defeats the purpose of using Lustre which separates metadata > from data. You can still use the shown architecture but I will advise > MDS being primary on Node A with Node B acting as failover partner. > Similarly, Node B being primary for OSS with Node A being failover partner. > > Also, unlike Sun Cluster, both nodes in Lustre failover pair can not > talk to same storage simultaneously. They work as a active-passive pair > of nodes. Please refer to Lustre manual which explains failover in > detail (manual.lustre.org). Searching Lustre failover in Google shows > some interesting links with detailed examples. See > http://mergingbusinessandit.blogspot.com/2008/12/implementing-lustre-failove > r.html > >> >> >> how should I configure lustre to support failover/failout. Ideally >> single node failure should be transparent to Lustre client. >> >> could you please provide commands to configure MDS/OSS with failover >> support. >> >> > See Lustre manual. > > >> >> >> should I give same volume for both MDS/OSS ? >> >> > No. Usually OSS resides on RAID6 volume whereas MDS resides on RAID10 > volume. It can be from same storage box, ST2540 in your case. Lustre > benefits from having multiple OSS nodes where IO can be striped across OSTs. > > Cheers, > -Atul > >> >> >> / / >> >> cheers, >> >> __ >> >> /tharindu/ >> >> >> >> >> > **************************************************************************** > **************************************************************************** > *********** > >> "The information contained in this email including in any attachment >> is confidential and is meant to be read only by the person to whom it >> is addressed. If you are not the intended recipient(s), you are >> prohibited from printing, forwarding, saving or copying this email. If >> you have received this e-mail in error, please immediately notify the >> sender and delete this e-mail and its attachments from your computer." >> >> >> > **************************************************************************** > **************************************************************************** > *********** > >> ------------------------------------------------------------------------ >> >> _______________________________________________ >> Lustre-discuss mailing list >> [email protected] >> http://lists.lustre.org/mailman/listinfo/lustre-discuss >> >> > > > -- ================================== Atul Vidwansa Sun Microsystems Australia Pty Ltd Web: http://blogs.sun.com/atulvid Email: [email protected] _______________________________________________ Lustre-discuss mailing list [email protected] http://lists.lustre.org/mailman/listinfo/lustre-discuss
