Steps for hot pull are referenced in EMC Solutions Enabler Symmetrix Migration CLI guide. Since there are SCSI reservations on the disk, you will need to do complete shutdown of the cluster, create OR session and then bring it back up. Pace and Ceiling are explained in the same document. Quorum will be migrated using Windows cluster admin, this procedure is online.
One more question, if there are 100's of servers to be migrated using Open replicator and for example 1000 of Luns are allocated for those servers. So how many of these can be migrated in a single shot and which factor decides the capacity that can be migrated? So if i have to start the migration what is the decent capacity to start with?
i think the new code supports upto 1024 sessions but i would not want to test this limit . I think the right approach would be to migrate cluster by cluster. use ceiling If you plan to migrate too many hosts at once. you would not want to choke Front ends.
i have done hundreds of devices (at slow pace though not to impact production, using -precopy). When app was shutdown i would increase pace so it would finish faster and then activate the session.
Thanks once again. Suppose if i do open replicator hot pull from clariion to VMAX, kick start open replicator session for 1 cluster & wait till 100% migration is done and then go with the next cluster. Thats what you meant. Right? Suppose if FAs or Clariion ports are not highly utilized then can i combine few servers and migrate?
after smaller devices are completed... we can increase the pace to 3 (maximum)... if you have dedicated ports for OR then there is no issue at all.. on an average for 1.5 TB data to complete the migration it takes around 2 hours.
even if you have dedicated ports for OR you might be putting too much load on the source devices. We had a couple databases where we started OR at pace 5 and DBAs were screaming that response times went up ..so we had to back it down.
@dynamox , that is true in some cases.. if the db is shutdown and the host is down we can use the highest pace.. on a live db we should take things into consideration.
sauravrohilla
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Posted March 8th, 2013 03:00
there you go:
https://support.emc.com/docu7065_Migrating-Microsoft-Cluster-Server-using-EMC-Open-Replicator-for-Symmetrix-Technical-Note.pdf?language=en_US