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

HP STORAGEWORKS ENTERPRISE FILE SERVICES WAN ACCELERATOR DEPLOYMENT GUIDE 123
13 - TROUBLESHOOTING
D
EPLOYMENT PROBLEMS
page 47 and in the HP Enterprise File Services WAN Accelerator Management
Console User Guide.
For more information and examples, see Chapter 5, “Connection Forwarding.”
Solution: Use
Virtual In-Path
Deployment
Because a connection cannot be optimized unless packets traveling in both network
directions pass through the same client-side HP EFS WAN Accelerator and the same
server-side HP EFS WAN Accelerator, you can use a virtual in-path deployment to
solve network asymmetry.
For instance, in the network shown Figure 13-1 on page 122, changing the server-side
HP EFS WAN Accelerator that is deployed in-path on the top server-side path to a
virtual in-path deployment, as shown in the following figure, would ensure that all
server-side traffic passes through the server-side HP EFS WAN Accelerator.
Figure 13-2. Virtual In-Path Deployment to Solve Network Asymmetry
Virtual in-path deployment differs from a physical in-path deployment in that a packet
redirection mechanism is used to direct packets to HP EFS WAN Accelerators that are
not in the physical path of the client or server. Redirection mechanisms include a
Layer-4 switch (or server load balancer), Web Cache Communication Protocol
(WCCP), and Policy-Based Routing (PBR). These redirection mechanisms are
described in:
 Chapter 3, “Virtual In-Path Network Deployments”
 Chapter 4, “Out-of-Path Network Deployments”
 Chapter 6, “Policy-Based Routing Deployments”
 Chapter 7, “WCCP Deployments”
Solution:
Deploy a
Four-Port HP
EFS WAN
Accelerator
If you have a Four-Port Copper Gigabit-Ethernet Bypass HP EFS WAN Accelerator,
you can deploy it to solve network asymmetry in which a two-port HP EFS WAN
Accelerator or one of the solutions described in previous sections is not successful.
For example, instead of the two-port HP EFS WAN Accelerator deployed to one
server-side path as shown Figure 13-1 on page 122, you could deploy a four-port HP
EFS WAN Accelerator on the server-side of the network. All server-side traffic would
pass through the four-port HP EFS WAN Accelerator and asymmetric routing would
be eliminated.