HP StorageWorks Enterprise File Services WAN Accelerator 3.0.4 deployment guide (AG421-96001, March 2007)

90 8 - SERIAL CLUSTER AND CASCADE DEPLOYMENTS
Appliances in a cluster process the peering rules you specify in a spill-over fashion.
When the maximum number of TCP connections for an HP EFS WAN Accelerator is
reached, that appliance stops intercepting new connections and passes them on to the
next HP EFS WAN Accelerator in the cluster (as defined by the peer rule that you set).
This process continues until there are no more HP EFS WAN Accelerators available in
the cluster.
Figure 8-1. Serial Cluster
In this example, HP EFS WAN Accelerator1, HP EFS WAN Accelerator2, and HP EFS
WAN Accelerator3 are configured so that they do not answer probes from each other
and do not intercept inner connections from each other. Similarly, HP EFS WAN
Accelerator4, HP EFS WAN Accelerator5, and HP EFS WAN Accelerator6 are
configured so that they do not answer probes from each other and do not intercept inner
connections from each other. The HP EFS WAN Accelerators are configured to
perform auto-discovery so that they can find a peer HP EFS WAN Accelerator that is
available and that is on the other side of the Wide Area Network (WAN).
In serial cluster or cascade deployments:
 A cluster can be created on either the client side or on the server side.
 The peering rules table is a ordered list of rules and the first rule that matches the
rule is applied.
 In the case of a cascade cluster, only pass-through peering rules are used.
 To block interceptions on inner connections created by other HP EFS WAN
Accelerators in the same cluster, in-path rules are specified to pass-through
connections originating from those HP EFS WAN Accelerators.
A Basic Serial
Cluster
Deployment
The following example illustrates how to configure a cluster of three in-path HP EFS
WAN Accelerators in a data center.
Figure 8-2. Serial Cluster in a Data Center
This example has the following parameters: