Primary Node Configuration for Atlas Clusters
The primary node configuration in itself is rather simple. First, you must choose which B Series Appliance will serve as the primary node. Unless the deployment is for a small number of representatives, the primary node will ideally be a B400 B Series Appliance. A second, matching backup must be used for the pairing of the primary role in a failover relationship.
Since the primary node plays a role in every support session, the network in which that primary node resides should be a central location in relation to your network as a whole.
Once you have planned where your primary node will reside physically, the next step is to confirm the name of your support site. This hostname will serve as the central hub, essentially, where your customers will seek support (e.g., http://access.example.com). You must also have a canonical hostname registered in your DNS environment for each B Series Appliance in the cluster.
The primary node also has the capacity to handle support sessions just as a traffic node. If there are network or environmental conditions disrupting the availability of a traffic node (from a client’s point-of-view) then a support session can fall back to the primary B Series Appliance. In this scenario, the primary B Series Appliance handles all aspects of the session without utilizing a traffic node. An administrator can set how many concurrent sessions can fall back to the primary B Series Appliance at any given time.