I have four esxi 5.0 hosts connected to EMC VNX5300 box via FC and to IBM DS3512 box via iSCSI. There are several datastores located on each storage device containing several VMs. I use EMC VNX box as faster storage for Heartbeat. We need to power cycle EMC VNX5300 to fix some mostly cosmetic issue with it. I am wondering what would be the proper steps on VMware side to prepare to power cycle this box? I am planning to migrate a couple of mission critical VMs to slower IBM storage, also change Heartbeat datastores from EMC to IBM datastores. I also got OK to shut down all remaining VMs on EMC...Please share your thought 
Thanks a lot!