Redirect Policies - Alcatel 7710 SR OS Configuration Manual

Redirect Policies

Redirect policies define one or more cache server destinations and provides a method to determine
which destination is used. Redirection policies are used to identify cache servers (or other
redirection target destinations) and define health check test methods used to validate the ability for
the destination to receive redirected traffic. This destination monitoring greatly diminishes the
likelihood of a destination receiving packets it cannot process.
Redirection identifies packets to be redirected and specifies the method to reach the web cache
server. Packets are identified by IP filter entries. The redirection action is accomplished and
supported with Policy Based Routing. Only IP routed frames can be redirected. Bridged IP packets
that match the entry criteria will not be redirected.
Redirection policies can contain multiple destinations. Each destination is assigned an initial or
base priority describing its relative importance within the policy. The destination with the highest
priority value is selected.
There are no default redirect policies. Each redirect policy must be explicitly configured and
specified in an IP filter entry.
To facilitate redirection based on a redirection policy, an IP filter must be created and applied to
the appropriate ingress or egress IP interfaces where redirection is required. The entry criteria for
the filter entry must specify a redirect policy to enable the appropriate IP packets to be redirected
from the normal IP routing next hop. If packets do not meet any of the defined match criteria, then
those packets are routed normally through the destination-based routing process.
The redirection policy is referenced within the action context for an IP filter entry, binding the
filter entry to the policy and the IP destinations managed by the policy. The policy specifies the
destination IP address where the packets matching the filter entry will be redirected. When the
policy determines the destination for packets matching the filter, the action on the filter entry is
similar to provisioning that destination IP address as an indirect next hop Policy Based Route
(PBR) action.
7710 SR OS Router Configuration Guide
Filter Policies
Page 305