HP Enterprise File Services WAN Accelerator manual One-to-One Failover Deployment

If there are more than two possible paths, additional HP EFS WAN Accelerators must be installed on each path and configured as neighbors. Neighbors receive information in parallel (the delay introduced at connection set up is equal to the time it takes to get an acknowledgement from the furthest neighbor).

If one of the neighbor HP EFS WAN Accelerators reaches its optimization capacity limit, that HP EFS WAN Accelerator will not accept new connections, but it redirects packets to other neighbors for optimization.

One-to-One Failover Deployment

To ensure optimization in the event of a failure, a backup HP EFS WAN Accelerator can be added to each neighbor HP EFS WAN Accelerator in a one-to-one failover configuration.

In Figure 5-2there are two HP EFS WAN Accelerators on each path that are configured in a one-to-one failover mode. Each HP EFS WAN Accelerator must be a neighbor of the master and backup HP EFS WAN Accelerators on the other paths.

Figure 5-2.One-to-One Failover Deployment

HP EFS WAN Accelerator-2 and HP EFS WAN Accelerator-2B are configured as neighbors of HP EFS WAN Accelerator-1 which exchanges connection information with both of them so that if either HP EFS WAN Accelerator-2 or HP EFS WAN Accelerator-2B fails, the other redirects packets to HP EFS WAN Accelerator-1.

In Figure 5-2, packets from the server are redirected by HP EFS WAN Accelerator-2B unless it fails in which case they are redirected by HP EFS WAN Accelerator-2.

As long as one of the two failover HP EFS WAN Accelerators on each path is up, connections are intercepted. If the two HP EFS WAN Accelerators on the same path fail, connections stop being intercepted and optimized.

Configuring Connection Forwarding

The following section describes the basic steps for configuring connection forwarding.

HP STORAGEWORKS ENTERPRISE FILE SERVICES WAN ACCELERATOR 2.1.5 DEPLOYMENT GUIDE 41

5 - CONFIGURING CONNECTION FORWARDING