Filtering Dvmrp Reports - Juniper JUNOSE SOFTWARE FOR E SERIES 11.3.X - MULTICAST ROUTING CONFIGURATION GUIDE 2010-10-07 Configuration Manual

JunosE 11.3.x Multicast Routing Configuration Guide
ip dvmrp route-limit

Filtering DVMRP Reports

ip dvmrp accept-filter
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Use to limit the number of routes that the router can advertise on each interface.
Example
host1:boston(config)#ip dvmrp route-limit 5000
Use the no version to restore the default value, 7000 routes.
See ip dvmrp route-limit.
You can configure an interface to accept only reports with routes that appear on a
standard IP access list. You can refine the set of accepted routes further, by defining a
second access list of neighbors who can supply the specified routes.
For example, suppose you define an access list that specifies that the router accepts
only reports for the route 172.16.2.0/24. You then define a second access list that specifies
that only neighbors 192.168.1.1 and 193.168.1.1 can supply this route. If neighbor 192.168.2.2
supplies the route, the DVMRP router rejects this report.
You can also modify the value (distance) that the router associates with a DVMRP route
when it computes the RPF interface for the source of a multicast packet. By default, the
router associates a distance of 0 with DVMRP routes; this value specifies that the router
use DVMRP, rather than a unicast routing protocol, to transport multicast datagrams.
However, in a configuration where PIM discovers multicast routes and a unicast routing
protocol performs RPF lookups, you can increase the administrative distance to favor
the unicast protocol.
For information about defining access lists, see Configuring Routing Policy in the JunosE
IP Services Configuration Guide.
Use to filter routes in DVMRP reports in accordance with a standard IP access list.
Specify a standard IP access list of sources for which the interface can accept routes.
Specify a DVMRP administrative distance to favor a unicast routing protocol.
Specify a neighbor list to restrict the neighbors from which reports for routes on the
first list can be accepted.
Example
host1:boston(config-if)#ip dvmrp accept-filter boston-list 4 neighbor-list
boston-neighbors
Use the no version to disable a filter.
See ip dvmrp accept-filter.
Copyright © 2010, Juniper Networks, Inc.