I am looking to set up a Disaster Recovery for Exchange Infrastructure. We have MSX Servers in 2 Sites. Each Site will be Recovery Center for each other. I am planning to set up a block level MSX DR between the 2 Sites. The data stores are currently in EMC SAN. The 2 Sites are well connected with 45 Mbits/sec connection. The RTO and RPO is about 4 Hours. Disaster Recovery means in case of Earthquake, etc. not "I accidently deleted that one email I really need :) ....". Being said it is acceptable if Messaging System comes to life in about 8 Hours or so. 1) Has anyone set up a block level DR in MSX SAN environment? 2) What is the best third party application used? Please Help! Many Thanks. Symyuser