Switching to ALUA question

[billb]

We are planning on turning on the ALUA flag for our iGroups on our NetApp filers.  We need to be sure the PSP won't automatically change once the flag is enabled on the iGroup where the ESX servers live.  I assume the PSP won't change until after a reboot and we manually change it with the NetApp utilties?

[MartinAmaro]

PSP wont change. After the reboot SATP will change to VMW_SATP_ALUA and the PSP to VMW_PSP_MRU.

** If you are using Microsoft Clustering Service, then verify with the vendor if you should turn on ALUA, becuase you can find your self with disk failures in failover storage

Also it migh help to review the bestpracies for netpp and VMware

http://media.netapp.com/documents/tr-3749.pdf

And you migth want to look at VMware KB Article: 1010713

http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=101071...

[billb]

Thanks, I've read those over and over.  We're doing this in a cluster one host at a time to avoid VM downtime.  I just wanted to be sure when they flipped the bit for ALUA on the iGroup for all the ESX hosts that there wouldn't be any immedite uncontrolled changes to the PSP.  We're going to vacate one host at a time, reboot and setup the new PSP.

I understand the best practices of powering down all the VMs, but that just isn't an option here.