HP StorageWorks Enterprise File Services WAN Accelerator Deployment Guide (November 2005)

16 1 - DESIGNING AN HP EFS WAN ACCELERATOR DEPLOYMENT
 Server Locations. A central server location that remote offices access
data from. Typically, a server location is a data center serving branch
offices or regional offices that access data that is centrally located.
 Users and Servers. A site that has users and servers that are accessed
remotely. Typically, users and servers are in a regional office with
branch offices at remote sites that accesses data from remote sites and a
data center.
2. Determine what kind of WAN routing infrastructure you have. For
example, do you have one or two WAN routers?
3. How much bandwidth do you use? If you use large amounts of
bandwidth, you need to consider deploying multiple HP EFS WAN
Accelerators using a Layer-4 switch, Web Cache Communication Protocol
(WCCP), or deploying HP EFS WAN Accelerators in a static cluster.
4. Choose a network template:
 Physical In-Path. In a physical in-path deployment the HP EFS WAN
Accelerator is physically in the direct path between clients and servers.
The clients and servers continue to see client and server Internet
Protocol (IP) addresses. Physical in-path configurations are suitable for
any location where the total bandwidth is within the limits of the
installed HP EFS WAN Accelerator. For detailed information, see
Chapter 2, “In-Path Deployments.”
 Logical In-Path. In a logical in-path deployment the HP EFS WAN
Accelerator is logically in the path between clients and servers. In a
logical in-path deployment, clients and servers continue to see client
and server IP addresses. This 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 Layer-4
switches, Web Cache Communication Protocol (WCCP), and Policy-
Based Routing (PBR). For detailed information, see Chapter 3, “Logical
In-Path Network Deployments.”
 Out-of-Path. In an out-of-path deployment the HP EFS WAN
Accelerator is not in the direct path between the client and the server. In
an out-of-path deployment, the HP EFS WAN Accelerator acts as a
proxy. An out-of-path configuration is suitable for data center locations
where physical in-path or logical in-path configurations are not
possible. For detailed information, see Chapter 4, “Out-of-Path
Network Deployments.”
5. Determine how many HP EFS WAN Accelerators you need for your site:
 One HP EFS WAN Accelerator is typically deployed in network
environments with small to moderate bandwidth requirements.
 Two HP EFS WAN Accelerators are deployed for redundancy in
network environments where network outages cannot be tolerated.
 Two HP EFS WAN Accelerators are deployed in network
environments with multiple WAN links.