as-override
Syntax
as-override;
Hierarchy Level
[edit logical-systems logical-system-name protocols bgp
group
group-name],
[edit logical-systems logical-system-name protocols bgp
group
group-name neighbor address],
[edit logical-systems logical-system-name routing-instances routing-instance-name protocols
bgp
group
group-name],
[edit logical-systems logical-system-name routing-instances routing-instance-name protocols
bgp group group-name
neighbor
address],
[edit protocols bgp
group
group-name],
[edit protocols bgp group group-name
neighbor
address],
[edit routing-instances routing-instance-name protocols bgp
group
group-name],
[edit routing-instances routing-instance-name protocols bgp group group-name
neighbor
address]
Release Information
Statement introduced before Junos OS Release 7.4.
Statement introduced in Junos OS Release 9.0 for EX Series switches.
Description
Compare the AS path of an incoming advertised route with the AS number of the BGP
peer under the group and replace all occurrences of the peer AS number in the AS path
with its own AS number before advertising the route to the peer.
NOTE:
The as-override statement is specific to a particular BGP group. This
statement does not affect peers from the same remote AS configured in
different groups.
Enabling the AS override feature allows routes originating from an AS to be accepted by
a router residing in the same AS. Without AS override enabled, the routing device refuses
the route advertisement once the AS path shows that the route originated from its own
AS. This is done by default to prevent route loops. The
as-override
statement overrides
this default behavior.
Note that enabling the AS override feature may result in routing loops. Use this feature
only for specific applications that require this type of behavior, and in situations with
strict network control. One application is the IGP protocol between the provider edge
routing device and the customer edge routing device in a virtual private network. For more
information, see the
Junos MPLS Applications Configuration Guide
.
Required Privilege
Level
routing—To view this statement in the configuration.
routing-control—To add this statement to the configuration.
Related
Documentation
•
Configuring BGP Groups and Peers
1723
Copyright © 2010, Juniper Networks, Inc.
Chapter 73: Configuration Statements for Layer 3 Protocols
Summary of Contents for JUNOS OS 10.3 - SOFTWARE
Page 325: ...CHAPTER 17 Operational Mode Commands for System Setup 229 Copyright 2010 Juniper Networks Inc ...
Page 1323: ...CHAPTER 56 Operational Mode Commands for Interfaces 1227 Copyright 2010 Juniper Networks Inc ...
Page 2841: ...CHAPTER 86 Operational Commands for 802 1X 2745 Copyright 2010 Juniper Networks Inc ...
Page 3367: ...CHAPTER 113 Operational Mode Commands for CoS 3271 Copyright 2010 Juniper Networks Inc ...
Page 3435: ...CHAPTER 120 Operational Mode Commands for PoE 3339 Copyright 2010 Juniper Networks Inc ...
Page 3529: ...CHAPTER 126 Operational Mode Commands for MPLS 3433 Copyright 2010 Juniper Networks Inc ...