Hi Gary,
I am struggling a littlebit to get the information out of your post, but I try to help you out: We have mission critical stuff running and our maximum fixtime is three hours. Without anyone working for three days we would be down and out.
To provide the uptime we have mirrored storage in two locations in different buildings on site and disaster recovery site as well. SAN is dual fabric. ESX public LAN is available in both datacenters. We can move every vm between them. We can provide enough power to customers with one datacenter completely gone. We dont loose any data with both datacenters completely gone. Each datacenter has two independent USV-Units. Each Datacenter is powered by a electric generator offering 48h backup time without refuling.
In case we loose data on the mirrored storage we are not able to get business back to work that quick because our tape backup would be to slow the restore everything in time. Regardless of the fact we can restore at about 200 MB per second. Its just not fast enough. But we can back 1/3 back to work after three hours. And 2/3 after 8 hours.
As a staring point: Imagine a fire burns down a building OR a fire strikes everything down in a location which is electrial located. How long would it take to get back everything to normal?
Ingo