Multicast Routing Table Entries Overview; Multicast Routing Table Preferences Overview - Juniper NETWORK AND SECURITY MANAGER 2010.4 - CONFIGURING SCREENOS DEVICES GUIDE REV 01 Manual

Configuring ScreenOS Devices Guide

Multicast Routing Table Entries Overview

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Multicast Routing Table Preferences Overview

346
Multicast Routing Table Entries Overview on page 346
Configuring a Rendezvous Point to Group Mappings (NSM Procedure) on page 342
Configuring Acceptable Groups (NSM Procedure) on page 343
Use static multicast routes to forward multicast data from hosts on interfaces in IGMP
router proxy mode to routers upstream on the interfaces in IGMP host mode. (For
information about IGMP proxy, see "Configuring IGMP Proxy (NSM Procedure)" on
page 339).
Multicast Route Overview on page 337
Multicast Routing Table Preferences Overview on page 346
You can configure the following settings for the multicast routing table:
Enable Multiple Incoming Interfaces—Select this option to permit multiple routes with
different incoming interfaces for the same source and multicast group.
Maximum Entries—Enter the maximum number of route entries you want the multicast
routing table to hold. By default, this option is set to 4096.
Negative Mroute Cache—Select this option to store unrouteable multicast packets in
a cache until a multicast route can be established for the packet. For example, the
security device might be unable to immediately route a multicast packet when:
The IGMP proxy receives a data packet for which it has no interested member. The
device creates a negative mroute entry for the packet and stores the packet in the
negative mroute cache. When the IGMP proxy receives a group join for the source
(or source and group), the device automatically forwards the cached packet.
The device receives a data packet from a locally connected PIM-SM but does not
have a group RP mapping for that group. The device creates a negative mroute entry
for the packet and stores the packet in the negative mroute cache. When the device
learns the RP mapping, it automatically registers and forwards the packet.
In an active-active NSRP configuration, the device that is not responsible for
forwarding packets receives a multicast data packet. The device creates a negative
mroute entry for the packet and stores the packet in the negative mroute cache.
When the device that is responsible for forwarding packets learns of the group interest
for the data packet, it forwards the packet.
When you enable Negative Mroute Cache, you can also configure a timer that controls
how the device ages unrouteable packets in the cache. By default, the timer is set
to 90 seconds, meaning that the device deletes a route entry in the cache after 90
seconds. The acceptable range is 10 to 180 seconds.
Copyright © 2010, Juniper Networks, Inc.