One word of advice: if using a SAN attached ESX deployment, make sure Disk.UseLunReset is set to 1 (default = 1) and Disk.UseDeviceReset is set to 0 (Defaults to 1). The reason to disable the Disk.UseDeviceReset param is because it does a complete SCSI bus reset. All SCSI reservations will be cleared, not for a a specific LUN but for the complete device. This could disrupt your SAN fabric. I would suggest setting the ESX host in maintenance mode and reboot it afterwards. See also page 118 of the Fibre Channel SAN Configuration guide or Yellow Bricks post on the topic for more info.
Alternatively, you can also set this via the Service Console by issuing the following commands:
esxcfg-advcfg -s 1 /Disk/UseLunReset
esxcfg-advcfg -s 0 /Disk/UseDeviceReset
service mgmt-vmware restart