Juniper JUNOSE 11.2.X BGP AND MPLS, Configuration Manual

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Specifying a Single-Hop Connection for IBGP Peers
IBGP peers are multihop by default. However, you can use the neighbor ibgp-single-hop
command to enable single-hop connections for IBGP peers.
neighbor ibgp-singlehop
•
Use to specify an internal BGP peer as a single-hop peer for IBGP sessions.
•
If you specify a BGP peer group by using the peerGroupName argument, all the members
of the peer group inherit the characteristic configured with this command unless it is
overridden for a specific peer.
•
If the neighbor session type is anything other than internal BGP, issuing this command
generates an error message.
•
This command takes effect immediately and automatically bounces the BGP session.
•
Example
host1(config-router)# neighbor 192.168.32.15 ibgp-singlehop
•
Use the no version to restore the default behavior, wherein the internal peer cannot be
a single-hop peer. Use the default version to remove the explicit configuration from
the peer or peer group and reestablish inheritance of the feature configuration.
•
See neighbor ibgp-singlehop
Controlling the Number of Prefixes
As the routing table increases in size, the processor and memory resources required to
process routing information increases. Some peers send so much routing information
that a BGP speaker can be overwhelmed by the updates. You can use the
neighbor
maximum-prefix command to limit how many prefixes can be received from a neighbor.
The router resets the BGP connection when the specified maximum is exceeded. You
can use the
warning-only keyword to log a warning rather than reset the connection.
You can also configure the router so that a warning is logged when a specified percentage
of the maximum is exceeded.
In the following example, the router is configured to reset the BGP connection when it
receives more than 1,000 prefixes from its neighbor at 2.2.2.2:
host1(config)# router bgp 100
host1(config-router)# neighbor 2.2.2.2 maximum-prefix 1000
neighbor maximum-prefix
•
Use to control how many prefixes can be received from a neighbor.
•
If you specify a BGP peer group by using the peerGroupName argument, all the members
of the peer group inherit the characteristic configured with this command unless it is
overridden for a specific peer.
•
By default, BGP checks the maximum prefix limit only against accepted routes. You
can specify the
strict keyword to force BGP to check the maximum prefix against all
Copyright © 2010, Juniper Networks, Inc. 34
JunosE 11.2.x BGP and MPLS Configuration Guide