Chapter 13: IP Policy-Based Forwarding Configuration Guide

To set the IP policy action with respect to dynamic or statically configured routes, enter one of the following commands in Configure mode:

Cause packets matching the

ip-policy <name> permit acl <profile> action

profile to use the IP policy route

policy-first

first. If the next-hop gateway is

 

not reachable, use the dynamic

 

route instead.

 

 

 

Route packets matching the

ip-policy <name> permit acl <profile> action

profile using dynamic routes

policy-last

first. If a dynamic route is not

 

available, then route packets

 

matching the profile using the IP

 

policy gateway.

 

 

 

Cause packets matching the

ip-policy <name> permit acl <profile> action

profile to use the IP policy route.

policy-only

If the next-hop gateway is not

 

reachable, then drop the packets.

 

 

 

Drop packets matching the

ip-policy <name> permit acl <profile> next-

profile.

hop-list null

 

 

Drop packets that do not match

ip-policy <name> permit everything-else

any profile.

next-hop-list null

 

 

Checking the Availability of Next-hop Gateways

The SSR can check the availability of next-hop gateways by querying them with ICMP_ECHO_REQUESTS. Only gateways that respond to these requests are used for forwarding packets. To configure the SSR to do this, enter the following command in Configure mode:

Periodically check the availability of next-hop gateways.

ip-policy <name> set pinger on

Note: Some hosts may have disabled responding to ICMP_ECHO packets. Make sure each next-hop gateway can respond to ICMP_ECHO packets before using this option.

Applying an IP Policy to an Interface

After you define the IP policy, it must be applied to an inbound IP interface. Once the IP policy is applied to the interface, packets start being forwarded according to the IP policy.

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Cabletron Systems SmartSwitch manual Applying an IP Policy to an Interface, Checking the Availability of Next-hop Gateways