Cisco 5505 - ASA Firewall Edition Bundle, Cli Configuration Manual

Page: 726 / 2164

1-14
Cisco ASA Series CLI Configuration Guide
Chapter 1 Configuring Multicast Routing
Customizing Multicast Routing
Detailed Steps
Configuring a Multicast Boundary
Address scoping defines domain boundaries so that domains with RPs that have the same IP address do
not leak into each other. Scoping is performed on the subnet boundaries within large domains and on the
boundaries between the domain and the Internet.
You can set up an administratively scoped boundary on an interface for multicast group addresses by
entering the multicast boundary command. IANA has designated the multicast address range from
239.0.0.0 to 239.255.255.255 as the administratively scoped addresses. This range of addresses can be
reused in domains administered by different organizations. The addresses would be considered local, not
globally unique.
A standard ACL defines the range of affected addresses. When a boundary is set up, no multicast data
packets are allowed to flow across the boundary from either direction. The boundary allows the same
multicast group address to be reused in different administrative domains.
You can configure, examine, and filter Auto-RP discovery and announcement messages at the
administratively scoped boundary by entering the
filter-autorp keyword. Any Auto-RP group range
announcements from the Auto-RP packets that are denied by the boundary ACL are removed. An
Auto-RP group range announcement is permitted and passed by the boundary only if all addresses in the
Auto-RP group range are permitted by the boundary ACL. If any address is not permitted, the entire
group range is filtered and removed from the Auto-RP message before the Auto-RP message is
forwarded.
To configure a multicast boundary, enter the following command:
Command Purpose
Step 1
access-list pim_nbr deny router-IP_addr
PIM neighbor
Example:
hostname(config)# access-list pim_nbr deny
10.1.1.1 255.255.255.255
Uses a standard access list to define the routers that you want to
have participate in PIM.
In the example, the following access list, when used with the pim
neighbor-filter command, prevents the 10.1.1.1 router from
becoming a PIM neighbor.
Step 2
pim bidirectional-neighbor-filter pim_nbr
Example:
hostname(config)# interface
GigabitEthernet0/3
hostname(config-if)# pim bidirectional
neighbor-filter pim_nbr
Filters neighbor routers.
In the example, the 10.1.1.1 router is prevented from becoming a
PIM bidirectional neighbor on interface GigabitEthernet0/3.
Command Purpose
multicast boundary acl [ filter-autorp ]
Example:
hostname(config-if)# multicast boundary
acl1 [filter-autorp]
Configures a multicast boundary.