Reference Guide
592 | Multicast Source Discovery Protocol (MSDP)
www.dell.com | support.dell.com
Preventing MSDP from Caching a Local Source
You can prevent MSDP from caching an active source based on source and/or group. Since the source is
not cached, it is not advertised to remote RPs.
When you apply this filter, the SA cache is not affected immediately. When sources which are denied by
the ACL time out, they are not refreshed. Until they time out, they continue to reside in the cache. To apply
the redistribute filter to entries already present in the SA cache, first clear the SA cache. You may
optionally store denied sources in the rejected SA cache.
Figure 31-12. Preventing MSDP from Caching a Local Source
Preventing MSDP from Caching a Remote Source
In Figure 31-14, R1 is advertising source 10.11.4.2. It is already in the SA cache of R3 when an ingress SA
filter is applied to R3. The entry remains in the SA cache until it expires; it is not stored in the rejected SA
cache.
Task Command Syntax Command Mode
OPTIONAL: Cache sources that are denied by the
redistribute list in the rejected SA cache.
ip msdp cache-rejected-sa
CONFIGURATION
Prevent the system from caching local SA entries based
on source and group using an extended ACL.
ip msdp redistribute list
CONFIGURATION
Task Command Syntax Command Mode
OPTIONAL: Cache sources that are denied by the
SA filter in the rejected SA cache.
ip msdp cache-rejected-sa
CONFIGURATION
Prevent the system from caching remote sources
learned from a specific peer based on source and
group.
ip msdp sa-filter list out peer list ext-acl
CONFIGURATION
R1_E600(conf)#do show run msdp
!
ip multicast-msdp
ip msdp peer 192.168.0.3 connect-source Loopback 0
ip msdp redistribute list mylocalfilter
ip msdp cache-rejected-sa 1000
R1_E600(conf)#do show run acl
!
ip access-list extended mylocalfilter
seq 5 deny ip host 239.0.0.1 host 10.11.4.2
seq 10 deny ip any any
R1_E600(conf)#do show ip msdp sa-cache
R1_E600(conf)#do show ip msdp sa-cache rejected-sa
MSDP Rejected SA Cache
1 rejected SAs received, cache-size 1000
UpTime GroupAddr SourceAddr RPAddr LearnedFrom Reason
00:02:20 239.0.0.1 10.11.4.2 192.168.0.1 local Redistribute