Administrator Guide
Version Description
7.8.1.0 Introduced on the S-Series.
7.7.1.0 Introduced on the C-Series.
Usage Information
To determine a BGP session ap, both a route-down event and a subsequent route-up event corresponding to a
single route are considered. As a result, a ap event is penalized only one time during the route-down event. The
subsequent route-up event corresponding to the same route is not considered as a ap and is not penalized.
The history paths that the show ip bgp command displays contain only the prex and the next-hop information.
The next-hop information shows the ip address of the neighbor. It does not show the actual next-hop details.
The following describes the show ip bgp damp command shown in the following example.
Field Description
Network Displays the network ID to which the route is dampened.
From Displays the IP address of the neighbor advertising the dampened route.
Reuse Displays the hour:minutes:seconds until the dampened route is available.
Path Lists all the ASs the dampened route passed through to reach the destination network.
Example
Dell# show ip bgp dampened-paths
BGP local RIB : Routes to be Added 0, Replaced 0, Withdrawn 0
BGP local router ID is 192.168.11.5
Status codes: s suppressed, S stale, d dampened, h history, * valid, > best
Path source: I - internal, a - aggregate, c - confed-external, r -
redistributed
n - network, D - denied, S - stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network From Reuse Path
d 55.0.0.0/24 172.16.0.2 00:36:23 200
Dell#
BGP Extended Communities (RFC 4360)
BGP Extended Communities, as dened in RFC 4360, is an optional transitive BGP attribute.
BGP Extended Communities provides two major advantages over Standard Communities:
• The range is extended from 4-octet (AA:NN) to 8-octet (Type:Value) to provide enough number communities.
• Communities are structured using a new “Type” eld (1 or 2-octets), allowing you to provide granular control/lter routing information
based on the type of extended communities.
456
Border Gateway Protocol