HP StorageWorks Enterprise File Services WAN Accelerator 2.1.5 deployment guide (June 2006)

HP STORAGEWORKS ENTERPRISE FILE SERVICES WAN ACCELERATOR 2.1.5 DEPLOYMENT GUIDE 65

7 - WCCP DEPLOYMENTS

The HP EFS WAN Accelerators use the following methods to communicate with

routers:

 Unicast (User Datagram Protocol Packets). The HP EFS WAN Accelerator is

configured with the IP address of each router. If additional routers are added to

the service group, they must be added on each HP EFS WAN Accelerator.

 Multicast. The HP EFS WAN Accelerator is configured with a multicast group.

If additional routers are added, you do not need to add or change configuration

settings on the HP EFS WAN Accelerators.

All Transmission Control Traffic (TCP) traffic is redirected by default. You can

configure specific source or destination ports to be redirected. For detailed

information, see “TCP Port Redirection” on page 80.

For other types of redirection filtering such as the Internet Protocol (IP) address, you

configure Access Control Lists (ACLs) on the routers and add it to the service group.

For detailed information, see “Specific Traffic Redirection” on page 81.

Traffic is redirected using one of the following schemes:

 gre (Generic Routing Encapsulation). Each data packet is encapsulated in a

GRE packet with the HP EFS WAN Accelerator IP address configured as the

destination. This scheme is applicable to any network.

 l2 (Layer-2). Each packet Media Access Control (MAC) address is rewritten with

an HP EFS WAN Accelerator MAC address. This scheme is possible only if the

HP EFS WAN Accelerator is connected to a router at Layer-2.

 either. The either value uses l2 (Layer-2) first—if Layer-2 is not supported, gre

is used.

You can load-balance using WCCP. Traffic is redirected based on a hashing scheme

and the weight of the HP EFS WAN Accelerators. You can hash on a combination of

the source IP address, destination IP address, source port, or destination port. The

default weight is based on the HP EFS WAN Accelerator model number. (The weight

is heavier for models that support more connections.) You can modify the default

weight. For detailed information, see “Load Balancing” on page 81.

You can also provide failover support using WCCP. In a failover configuration, the HP

EFS WAN Accelerators periodically announce themselves to the routers. If an HP EFS

WAN Accelerator fails, traffic is redirected to the working HP EFS WAN Accelerators.

To configure failover support where the passive HP EFS WAN Accelerator takes over

if there is a failure in the active HP EFS WAN Accelerator, you simply configure the

weight for the backup HP EFS WAN Accelerator to be 0. For detailed information, see

“Failover Support” on page 81.

Basic Steps The following steps summarize how to configure WCCP on a client-side HP EFS

WAN Accelerator with an out-of-path server-side HP EFS WAN Accelerator.

IMPORTANT: This is an example of one type of WCCP deployment. You can also have

deployments with both HP EFS WAN Accelerators configured as in-path devices and WCCP

configured on one of them. Contact HP technical support for further information at http://