To specify that a community’s attribute should be sent to a BGP neighbor, use the
neighbor send-community
command in address family or router configuration mode. To remove the entry, use the
no
form of this command.
By default the communities attribute is sent to all peers.
Processing sent and received MEDs
Syntax:
[no] neighbor
ipv4-addr
use-med
Processes sending of MEDS and handles received MEDs. When two routes to the same destination are received
from different peers within the same peer as, they may have different MEDs. When choosing between these
routes, assuming that nothing else makes one preferable to the other (such as configured policy), the values of
the differing MEDs are used to choose which route to use. In this comparison, the route with the lowest MED is
preferred. Routes without MEDs are treated as having a MED value of zero. By default, MEDs are used to choose
which route to use.
Setting the timer for a BGP peer
Syntax:
[no] neighbor
ipv4-addr
timers
keep-alive
hold-time
To set the timers for a specific BGP peer, use the
neighbor timers
command in router configuration mode. To
clear the timers for a specific BGP peer, use the
no
form of this command. The values of keep-alive and hold-time
default to 60 and 180 seconds, respectively.
The timers configured for a specific neighbor override the timers configured for all BGP neighbors using the
timers
command.
Resetting BGP peering sessions
Syntax:
clear ip bgp [neighbor
ipv4-addr
] [soft]
Resets BGP peering sessions; sends route refresh requests if ‘soft’.
Enabling or disabling multi-hop peering
Syntax:
[no] neighbor
ipv4-addr
ibgp-multihop [
ttl
]
Enables or disables multi-hop peering with the specified EBGP peer, and optionally indicates the maximum
number of hops (TTL.)
Using the router's outbound interface address as next hop
Syntax:
[no] neighbor
ipv4-addr
next-hop-self
Forces BGP to use the router's outbound interface address as the next hop for the route updates to the peer.
Chapter 17 Border Gateway Protocol (BGP)
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