Exchange 2010, Creating DAGs and Quorum Shares

• For a DAG it wants a Quorum computer, this need to be another device that isn't part of the dag group, is part of the domain and must have a little bit of exchange2010 installed on it
  • I found the best way (and the recommended best practice) to install just hub transport role on another computer in whichever location you want to be primary
  • It creates a Quorum share in the root of the C drive, all of the other machines and that machine need access and permissions to this folder, I found it best to just open it up to all users
  • Interestingly it appears to load some of the Microsoft clustering functionality, as it creates a cluster name (actual computer name) on the network that represents the DAG as a single entity.
• Exchange 2010 needs full RPC access between servers, when dealing with ISA/TMG it is important to enable the ExchangeRPC protocols (if present) which are extended beyond normal RPC. This may also include enabling 64bit RPC stuff
• First you create a DAG, then you add servers to it, once you've done that, you can create database copies of any of the databases on member server to other member servers, once you've done that, you can activate or failover databases between servers
• To maintain local failover precedence over WAN failover (since we have 1st & 2nd servers in Tampa and the 3rd in PH), you must enable DAC
• DAC requires at least 3 E2k10 servers to activate and then will force this precedence, it knows based on AD sites, which are based on subnets (AD figures that out), the command is: " Set-DatabaseAvailabilityGroup -Identity [dag name] -DatacenterActivationMode DagOnly"