Good question. I dont have one right now. But this is what I would check:
1 .Configuration of all storage arrays. ip’s, passwords, raid groups, physical disks, storage processors, luns, connected hosts, support contact and information needed to contact spport.
2. SAN switch, configuration, # of ports, ports used, connected HBA’s or storage controllers, model, support information.
3. End to end storage layout diagram.
4. Metrics pertaining to iops per port, aggregated to iops per switch. Disk space utilization, RAID group utilization, Storage processor iops, %bandwidth used.
You get the idea. Start small, and you can keep adding to it.