Gabrie van Zanten of Gabes Virtual World comments:

Running a VMware vSphere Metro Storage Cluster (VMware vMSC) makes it possible to move VMs between two geographical locations without downtime. In a Metro Storage Cluster a vSphere Cluster consists of ESXi hosts from both locations with shared storage that is stretched over these locations. Using a VMware Metro Storage Cluster makes your environment even more resilliant against failures and can help you get up and running again much faster should a disaster occur.

Tagging everything with the proper location will save you a lot of time when disaster strikes. The less thinking you have to do, the better.

Read more at: Manage your VMware Metro Storage Cluster with Tags