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Checking the availability of next-hop gateways, Applying an ip policy to an interface – Cabletron Systems SmartSwitch User Manual

Page 213

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SmartSwitch Router User Reference Manual

213

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:

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:

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.

Cause packets matching the
profile to use the IP policy route
first. If the next-hop gateway is
not reachable, use the dynamic
route instead.

ip-policy

permit acl

action

policy-first

Route packets matching the
profile using dynamic routes
first. If a dynamic route is not
available, then route packets
matching the profile using the IP
policy gateway.

ip-policy

permit acl

action

policy-last

Cause packets matching the
profile to use the IP policy route.
If the next-hop gateway is not
reachable, then drop the packets.

ip-policy

permit acl

action

policy-only

Drop packets matching the
profile.

ip-policy

permit acl

next-

hop-list null

Drop packets that do not match
any profile.

ip-policy

permit everything-else

next-hop-list null

Periodically check the
availability of next-hop
gateways.

ip-policy

set pinger on