Configuring Prefix Peering; Configuring Bgp Authentication - Cisco Nexus 7000 Series Configuration Manual

Chapter 11 Configuring Advanced BGP
S e n d d o c u m e n t c o m m e n t s t o n e x u s 7 k - d o c f e e d b a c k @ c i s c o . c o m .

Configuring Prefix Peering

BGP supports the definition of a set of peers using a prefix for both IPv4 and IPv6. This feature allows
you to not have to add each neighbor to the configuration.
When defining a prefix peering, you must specify the remote AS number with the prefix. BGP accepts
any peer that connects from that prefix and autonomous system if the prefix peering does not exceed the
configured maximum peers allowed.
When a BGP peer that is part of a prefix peering disconnects, Cisco NX-OS holds its peer structures for
a defined prefix peer timeout value. An established peer can reset and reconnect without danger of being
blocked because other peers have consumed all slots for that prefix peering.
To configure the BGP prefix peering timeout value, use the following command in router configuration
mode:
Command
timers prefix-peer-timeout value
Example:
switch(config-router-neighbor)# timers
prefix-peer-timeout 120
To configure the maximum number of peers, use the following command in neighbor configuration
mode:
Command
maximum-peers value
Example:
switch(config-router-neighbor)#
maximum-peers 120
This example shows how to configure a prefix peering that accepts up to 10 peers:
switch(config)# router bgp 65536
switch(config-router)# timers prefix-peer-timeout 120
switch(config-router)# neighbor 10.100.200.0/24 remote-as 65536
switch(config-router-neighbor)# maximum-peers 10
switch(config-router-neighbor)# address-family ipv4 unicast
switch(config-router-neighbor-af)#
Use the show ip bgp neighbor command to show the details of the configuration for that prefix peering
with a list of the currently accepted instances and the counts of active, maximum concurrent, and total
accepted peers.

Configuring BGP Authentication

You can configure BGP to authenticate route updates from peers using MD5 digests.
To configure BGP to use MD5 authentication, use the following command in neighbor configuration
mode:
OL-20002-02
Purpose
Configures the timeout value for prefix peering.
The range is from 0 to 1200 seconds. The default
value is 30.
Purpose
Configures the maximum number of peers for this
prefix peering. The range is from 1 to 1000.
Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide, Release 4.x
Configuring Advanced BGP
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