Preventing Dynamic Route Distribution; Exchanging Dvmrp Unicast Routes - Juniper JUNOSE 11.0.X MULTICAST ROUTING Configuration Manual

JUNOSe 11.0.x Multicast Routing Configuration Guide

Preventing Dynamic Route Distribution

By default, if you make changes to a route map, the router dynamically redistributes
the routes in DVMRP. To prevent this dynamic redistribution, use the
disable-dynamic-redistribute command.
disable-dynamic-redistribute

Exchanging DVMRP Unicast Routes

DVMRP maintains its own unicast routing table, based on distance vector calculations.
The routing table defines the best-known distance to each destination and how to
get there. The router updates the table by exchanging information with its neighbors.
The DVMRP routing table is used solely for RPF lookups.
By default, if DVMRP owns an interface, that interface exchanges DVMRP unicast
routes with its neighbors, and you cannot disable the exchange of routes. However,
you can enable and disable the exchange of DVMRP unicast routes on interfaces that
DVMRP does not own.
When an interface exchanges DVMRP routes, the router obtains routes from DVMRP
report messages and stores them in its DVMRP routing table. Other multicast
protocols, such as PIM, can then use these routes for RPF lookups. With this feature,
PIM can use the DVMRP routing table even when the router is not running DVMRP.
All interfaces, including tunnels, support DVMRP unicast routing. DVMRP tunnels
use DVMRP multicast routing to support DVMRP unicast routing.
ip dvmrp unicast-routing
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Preventing Dynamic Route Distribution

host1:boston(config-if)#ip dvmrp announce-filter boston-list
Use the no version to enable the interface to advertise all DVMRP routes that it
has learned.
See ip dvmrp announce-filter.
Use to halt the dynamic redistribution of routes that are initiated by changes to
a route map; dynamic redistribution is enabled by default.
Example
host1(config-router)#disable-dynamic-redistribute
There is no no version.
See disable-dynamic-redistribute.
Use to enable the exchange of DVMRP unicast routes on an interface not owned
by DVMRP.
Example
host1:boston(config-if)#ip dvmrp unicast-routing