Enabling cooperative filtering – Brocade TurboIron 24X Series Configuration Guide User Manual
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Brocade TurboIron 24X Series Configuration Guide
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Filtering
When you enable cooperative filtering, the Layer 3 Switch advertises this capability in its Open
message to the neighbor when initiating the neighbor session. The Open message also indicates
whether the Layer 3 Switch is configured to send filters, receive filters or both, and the types of
filters it can send or receive. The Layer 3 Switch sends the filters as Outbound Route Filters (ORFs)
in Route Refresh messages.
To configure cooperative filtering, perform the following tasks on the Layer 3 Switch and on its
BGP4 neighbor:
•
Configure the filter.
NOTE
The current release supports cooperative filtering only for filters configured using IP prefix lists.
•
Apply the filter as in inbound filter to the neighbor.
•
Enable the cooperative route filtering feature on the Layer 3 Switch. You can enable the Layer 3
Switch to send ORFs to the neighbor, to receive ORFs from the neighbor, or both. The neighbor
uses the ORFs you send as outbound filters when it sends routes to the Layer 3 Switch.
Likewise, the Layer 3 Switch uses the ORFs it receives from the neighbor as outbound filters
when sending routes to the neighbor.
•
Reset the BGP4 neighbor session to send and receive ORFs.
•
Perform these steps on the other device.
NOTE
If the Layer 3 Switch has inbound filters, the filters are still processed even if equivalent filters have
been sent as ORFs to the neighbor.
Enabling cooperative filtering
To configure cooperative filtering, enter commands such as the following.
TurboIron(config)#ip prefix-list Routesfrom10234 deny 10.20.20.0/24
TurboIron(config)#ip prefix-list Routesfrom10234 permit 0.0.0.0/0 le 32
TurboIron(config)#router bgp
TurboIron(config-bgp-router)#neighbor 10.2.3.4 prefix-list Routesfrom10234 in
TurboIron(config-bgp-router)#neighbor 10.2.3.4 capability orf prefixlist send
The first two commands configure statements for the IP prefix list Routesfrom10234. The first
command configures a statement that denies routes to 10.20.20.0/24. The second command
configures a statement that permits all other routes. (Once you configure an IP prefix list
statement, all routes not explicitly permitted by statements in the prefix list are denied.)
The next two commands change the CLI to the BGP4 configuration level, then apply the IP prefix list
to neighbor 10.2.3.4. The last command enables the Layer 3 Switch to send the IP prefix list as an
ORF to neighbor 10.2.3.4. When the Layer 3 Switch sends the IP prefix list to the neighbor, the
neighbor filters out the 10.20.20.x routes from its updates to the Layer 3 Switch. (This assumes
that the neighbor also is configured for cooperative filtering.)
The
of a peer group of neighbors.
The send | receive parameter specifies the support you are enabling:
•
send – The Layer 3 Switch sends the IP prefix lists to the neighbor.
•
receive – The Layer 3 Switch accepts filters from the neighbor.