Avaya 580, 882 Creating a Static Route to a Null Interface

12-20 User Guide for the Avaya P580 and P882 Multiservice Switches, v6.1
Chapter 12
CLI Commands To create and show IP static routes use the following CLI commands:
■To create an IP static route, (configure)# ip route <ip-addr>
<mask> <next hop IP address> <cost> <preference>
■To view all IP static routes that are configured on the switch,
(configure)# show ip route static
Creating a Static Route to a Null Interface
Overview
A null interface is a virtual interface that discards IP packets and is used to
prevent routing loops from occurring in the network.
You do not assign the null interface an IP address. Instead, you create a
static route for a network and set the next hop to the null interface (null0).
Figure 12-7 shows an example of a null interface preventing loops in the
network.
Table 12-5. IP Static Route Parameters
Field Explanation
Network Address Enter an IP network address for your IP static route.
Mask Enter an IP subnet mask for your IP static route.
Next-Hop Address Enter an IP address for the gateway associated with
the IP static route.
The default setting is null 0, which creates a discard
route. For information on creating a discard route, see
“Creating a Static Route to a Null Interface.”
Cost Enter the metric between this router and the
destination.
Preference Select a low or high routing preference from the
Preference field pull-down menu.
Preference overrides cost. If two routes of the same
preference are present, the switch uses the route that
has the lower cost.