Static Routes; Static Routes And High Availability Mode; Black Hole Static Routes - Avaya 8800 Configuration Manual

Static routes

You can use static routes to manually create routes to a destination IP address.
You can use a static default route to specify a route to all networks for which no explicit routes
exist in the Forwarding Information Base or the routing table. This route is, by definition, a route
with the prefix length of zero (RFC 1812). You can configure the Ethernet Routing Switch
8800/8600 with any route by using the IP static routing table.
To create a default static route, you must configure the destination address and subnet mask
to 0.0.0.0.
You can configure a static route with a next-hop that is not directly connected, but that hop
must be reachable. Otherwise, the static route is not enabled.

Static routes and High Availability mode

High Availability (HA) mode supports the creation of static routes to enhance network stability.
When you configure a static route on a Master SF/CPU, the Standby SF/CPU has the same
setup through synchronization. You can use the local next-hop option to configure a static route
with or without a local next hop.
For more information about HA mode and support, see Avaya Ethernet Routing Switch
8800/8600 Administration, NN46205-605 and Avaya Ethernet Routing Switch 8800/8600
Release Notes — Software Release 5.0, NN46205-402.

Black hole static routes

A black hole static route is a route with an invalid next hop. The switch drops packets destined
for this network.
While it aggregates or injects routes to other routers, the router itself may not have a path to
the aggregated destination. In such cases, the result is a black hole or a routing loop. To avoid
such loops, configure a black hole static route to the advertised destination.
You can configure a preference value for a black hole route. Configure that preference value
so that it is elected as the best route.
Before you add a black hole static route, ensure that no other static route to the same
destination is enabled. If such a route exists, you cannot add the black hole route.
Configuration — OSPF and RIP
Static routes
June 2011 19