cache-sa-state
To control cache source-active (SA) state on a router, use the cache-sa-state command in MSDP configuration mode. To return to the default behavior, use the no form of this command.
cache-sa-state {list access-list-number | rp-list access-list-name}
no cache-sa-state {list access-list-number | rp-list access-list-name}
Syntax Description
list access-list-number |
Specifies an IP access list that defines which (S, G) pairs to cache. |
rp-list access-list-name |
Specifies an access list name for the originating rendezvous point (RP). |
Command Default
The router creates SA state.
Command Modes
MSDP configuration
Command History
Release |
Modification |
---|---|
Release 7.0.12 |
This command was introduced. |
Usage Guidelines
When a new member joins a group immediately after an SA message arrives, latency may occur and an SA message may be missed. To overcome this problem, you can configure this command and the router will supply SA information (from cache memory) to the new member instead of requiring that the member wait until the next SA message is received.
The cache-sa-state command is required in every Multicast Source Discovery Protocol (MSDP) speaker, to cache SA messages received from peers.
Task ID
Task ID |
Operations |
---|---|
multicast |
read, write |
The following example shows how to configure the cache state for all sources in 10.0.0.0/16 sending to groups 224.2.0.0/16:
RP/0/0RP0RSP0/CPU0:router:hostname# configure
RP/0/0RP0RSP0/CPU0:router:hostname(config)# MSDP
RP/0/0RP0RSP0/CPU0:router:hostname(config-msdp)# cache-sa-state list 100
RP/0/0RP0RSP0/CPU0:router:hostname(config-msdp)# exit
RP/0/0RP0RSP0/CPU0:router:hostname(config)# ipv4
access-list 100 permit 10.0.0.0 0.0.255.255 224.2.0.0 0.0.255.255
Note |
The source and destination fields in the access list matches on the (S,G) fields in the SA messages. We recommend that the first address and mask field in the access list is used for the source and the second field in the access list is used for the group or destination. |