Reference Guide
View dampened paths
OS10# show ip bgp dampened-paths
BGP local router ID is 80.1.1.1
Status codes: s suppressed, S stale, d dampened, h history, * valid, > best
Origin codes: i - IGP, e - EGP, ? - incomplete
Network From Reuse Path
d* 3.1.2.0/24 80.1.1.2 00:00:12 800 9 8 i
d* 3.1.3.0/24 80.1.1.2 00:00:12 800 9 8 i
d* 3.1.4.0/24 80.1.1.2 00:00:12 800 9 8 i
d* 3.1.5.0/24 80.1.1.2 00:00:12 800 9 8 i
d* 3.1.6.0/24 80.1.1.2 00:00:12 800 9 8 i
Total number of prefixes: 5
Timers
To adjust the routing timers for all neighbors, congure the timer values using the timers command. If both the peers negotiate with
dierent keepalive and hold time values, the nal hold time value is the lowest values received. The new keepalive value is one-third of the
accepted hold time value.
• Congure timer values for all neighbors in ROUTER-NEIGHBOR mode.
timers keepalive holdtime
– keepalive — Time interval in seconds, between keepalive messages sent to the neighbor routers (1 to 65535, default 60).
– holdtime — Time interval in seconds, between the last keepalive message and declaring the router dead (3 to 65535, default
180).
View nondefault values
OS10# show running-configuration
...
neighbor 32.1.1.2
remote-as 103
timers 61 181
no shutdown
Neighbor soft-reconguration
BGP soft-reconguration allows for fast and easy route changes. Changing routing policies requires a reset of BGP sessions or the TCP
connection, for the policies to take eect.
Resets cause undue interruption to trac due to the hard reset of the BGP cache, and the time it takes to re-establish the session. BGP
soft-reconguration allows for policies to apply to a session without clearing the BGP session. You can perform a soft-reconguration on a
per-neighbor basis, either inbound or outbound. BGP soft-reconguration clears the policies without resetting the TCP connection. After
conguring soft-reconguration, use clear ip bgp to make the neighbor use soft reconguration.
When you enable soft-reconguration for a neighbor and you execute the clear ip bgp soft in command, the update database
stored in the router replays and updates are re-evaluated. With this command, the replay and update process triggers only if a route-refresh
request is not negotiated with the peer. If the request is negotiated after using the
clear ip bgp soft in command, BGP sends a
route-refresh request to the neighbor and receives all the peer’s updates.
To use soft reconguration, or soft reset without preconguration, both BGP peers must support the soft route refresh capability. The soft
route refresh advertises in the OPEN message sent when the peers establish a TCP session. To determine whether a BGP router supports
this capability, use the show ip bgp neighbors command. If a router supports the route refresh capability, the Received route
refresh capability from peer
message displays.
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Layer 3