Optional Gre Tunnel Features; Keepalive - Avaya G250 Administration

Accept policy.
●
Configure a policy rule on the source tunnel endpoint (router 1) that will cause the source
endpoint to not accept routing updates that include the source network (192.68.1.0). This
solution is for nested tunneling caused by RIP. For example, using the network shown in
Figure 34
activate it on the router RIP with the matching interface:
G350-001(super)# ip distribution access-list-name 1 "list #1"
Done!
G350-001(super)# ip distribution access-default-action 1 default-action-permit
Done!
G350-001(super)# ip distribution access-list 1 10 "deny" 192.68.1.0 0.0.0.255
Done!
G350-001(super)# router rip
G350-001(super router:rip)# distribution-list 1 in FastEthernet 10/2
Done!
G350-001(super router:rip)# exit
G350-001(super)#
Static route.
●
Configure a static rule on router 1 telling it the route for packets destined to the tunnel's
receiving endpoint (192.68.1.2). This route should be configured with a high route
preference. For example:
G350-001(super)# ip route 192.68.1.2 255.255.0.0 192.68.1.3 high permanent
Done!
G350-001(super)#

Optional GRE tunnel features

You can configure the following optional features in GRE tunnels:

keepalive

●
Dynamic MTU discovery
●
through the tunnel.
keepalive
The tunnel keepalive feature sends keepalive packets through the tunnel interface to determine
whether the tunnel is up or down. This feature enables the tunnel's source interface to inform
the host if the tunnel is down. When the tunnel keepalive feature is not active, if the tunnel is
down, the tunnel's local endpoint continues to attempt to send packets over the tunnel without
informing the host that the packets are failing to reach their destination.
Use the keepalive command in the context of the GRE tunnel interface to enable the tunnel
keepalive feature. Use the no form of this command to deactivate the feature.
as an illustration, you would configure the following policy rule on router 1 and
— enables periodic checking to determine if the tunnel is up or down.
— determines and updates the lowest MTU on the current route
Configuring GRE tunneling
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