CONFIGURING

Setting up cluster access for remote users
You can give remote users the benefits of a cluster by setting them up to access the cluster through a pass-through server. The pass-through server can redirect the users to a different server in the cluster if the original server is busy or not available. Unless you use a pass-through server, users will have to dial each cluster server individually and will not fail over if the server they call is not available.

The following figure shows a remote client calling a passthru server and having access to any server in a cluster. When connecting to the cluster in this way, failover and workload balancing are available to the remote client. Routing a remote client through a pass-through server to a cluster

Because remote clients can typically call only one server at a time, they cannot take advantage of a cluster of pass-through servers. However, you can set up a hunt group of pass-through servers to ensure that remote clients have high availability to pass-through servers.

If you do not have access to a pass-through server, users can still use their Replicator page to simulate failover if a cluster server is down. To replicate a mail database, for example, set up the Replicator page to call and replicate with the user's mail server, and then call and replicate with the server that contains the user's replica mail database. That way, if either server is available, the user will have access to the mail database. The call to the second server will take very little time if the first call was successful.

The following figure shows a remote client calling Server 1, which is the user's mail server, and then calling Server 2, which contains a replica of the user's mail database. Simulating pass-through for a remote client

Related concepts
Setting up a cluster