Border Gateway Protocol IPv4 (BGPv4) |
259
Use the following commands in the CONFIGURATION ROUTER BGP mode to configure BGP
confederations.
Use the
show config
command in the CONFIGURATION ROUTER BGP mode to view the
configuration.
Enable route flap dampening
When EBGP routes become unavailable, they “flap” and the router issues both WITHDRAWN and
UPDATE notices. A flap is when a route
•
is withdrawn
•
is readvertised after being withdrawn
•
has an attribute change
The constant router reaction to the WITHDRAWN and UPDATE notices causes instability in the BGP
process. To minimize this instability, you may configure penalties, a numeric value, for routes that flap.
When that penalty value reaches a configured limit, the route is not advertised, even if the route is up. In
FTOS, that penalty value is 1024. As time passes and the route does not flap, the penalty value decrements
or is decayed. However, if the route flaps again, it is assigned another penalty.
The penalty value is cumulative and penalty is added under following cases:
•
Withdraw
•
Readvertise
•
Attribute change
When dampening is applied to a route, its path is described by one of the following terms:
•
history entry—an entry that stores information on a downed route
•
dampened path—a path that is no longer advertised
•
penalized path—a path that is assigned a penalty
The CLI example below shows configuring values to start reusing or restarting a route, as well as their
default values.
Command Syntax
Command Mode
Purpose
bgp confederation identifier
as-number
CONFIG-ROUTER-
BGP
Specifies the confederation ID.
AS-number: 0-65535 (2-Byte) or 1-4294967295
(4-Byte)
bgp confederation peers
as-number
[...
as-number
]
CONFIG-ROUTER-
BGP
Specifies which confederation sub-AS are peers.
AS-number: 0-65535 (2-Byte) or 1-4294967295
(4-Byte)
All Confederation routers must be either 4-Byte or 2-Byte. You cannot have a
mix of router ASN support,
Summary of Contents for Force10 E300
Page 1: ...FTOS Configuration Guide FTOS 8 4 2 7 E Series TeraScale C Series S Series S50 S25 ...
Page 32: ...32 w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 132: ...132 802 1X w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 310: ...310 Configuration Replace and Rollback w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 330: ...330 Dynamic Host Configuration Protocol w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 402: ...402 High Availability w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 462: ...462 Interfaces w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 482: ...482 IPv4 Addressing w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 506: ...506 IPv6 Addressing w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 582: ...582 Layer 2 w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 642: ...642 Multicast Source Discovery Protocol w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 662: ...662 Multiple Spanning Tree Protocol w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 690: ...690 Object Tracking w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 754: ...754 PIM Dense Mode w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 784: ...784 PIM Source Specific Mode w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 800: ...800 Power over Ethernet w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 876: ...876 Quality of Service w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 892: ...892 Routing Information Protocol w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 1006: ...1006 Simple Network Management Protocol w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 1018: ...1018 SONET SDH w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 1048: ...1048 Broadcast Storm Control w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 1096: ...1096 Uplink Failure Detection UFD w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 1098: ...1098 Upgrade Procedures w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 1196: ...1196 C Series Debugging and Diagnostics w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 1252: ...1252 Standards Compliance w w w d e l l c o m s u p p o r t d e l l c o m ...
Page 1262: ...1262 Index w w w d e l l c o m s u p p o r t d e l l c o m ...