Steelhead Appliance Installation and Configuration Guide
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Overview of the Steelhead Appliance
Overview of the Steelhead Appliance
The Steelhead appliance is typically deployed on a LAN, with communication between appliances taking
place over a private WAN or VPN. Because optimization between Steelhead appliances typically takes
place over a secure WAN, it is not necessary to configure company firewalls to support Steelhead specific
ports.
Figure 1-1. Typical In-Path Deployment
For detailed information about how the Steelhead appliance works and deployment design principles, see
the Steelhead Appliance Deployment Guide.
The Auto-Discovery Process
Auto-discovery enables Steelhead appliances to automatically find remote Steelhead appliances and to
optimize traffic to them. Auto-discovery relieves you of having to manually configure the Steelhead
appliances with large amounts of network information (for example, multiple in-path rules). The auto-
discovery process enables you to control and secure connections, specify which traffic is optimized, and
specify how remote peers are selected for optimization. There are two types of auto-discovery, original and
enhanced.
Enhanced auto-discovery (RiOS v4.0.x or later) automatically discovers the last Steelhead appliance in the
network path of the TCP connection. In contrast, the original auto-discovery protocol automatically
discovers the first Steelhead appliance in the path. The difference is only seen in environments where there
are three or more Steelhead appliances in the network path for connections to be optimized. Enhanced auto-
discovery works with Steelhead appliances running the original auto-discovery protocol.
Configuring Optimization
You configure optimization of traffic using the Management Console or the Riverbed CLI. You configure
what traffic a Steelhead appliance optimizes and specify the type of action it performs using:
In-Path rules
. In-path rules determine the action a Steelhead appliance takes when a connection is
initiated, usually by a client. In-path rules are used only when a connection is initiated. Because
connections are usually initiated by clients, in-path rules are configured for the initiating, or client-side
Steelhead appliance. In-path rules determine Steelhead appliance behavior with SYN packets. You
configure one of the following types of in-path rule actions:
Auto
. Use the auto-discovery process to determine if a remote Steelhead appliance is able to
optimize the connection attempting to be created by this SYN packet.
Pass-through
. Allow the SYN packet to pass through the Steelhead appliance. No optimization is
performed on the TCP connection initiated by this SYN packet.
Fixed-Target
. Skip the auto-discovery process and use a specified remote Steelhead appliance as an
optimization peer. Fixed target rules require the input of at least one remote target Steelhead
appliance; an optional backup Steelhead appliance might also be specified.
