I'm preparing to do an upgrade in place from ESXi 3.5 to ESXi 4.0. The data stores are located on SAN. Some people (in this forum) mention disconnecting the datastores physically from the host and then readding them after the upgrade process. Official VMware upgrade guides don't mention that at all. Is it a good precaution? Has any of the experts done it? Is it as simple as unplugging the iSCSI cables from the host?