3Com Switch 7750 Configuration Guide Guide

350 CHAPTER 36: BGP CONFIGURATION
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CAUTION:
■ The reasonable maximum interval for sending Keepalive message is one third
of the Holdtime, and the interval cannot be less than 1 second, therefore, if the
Holdtime is not 0, it must be 3 seconds at least.
■ BGP soft reset can refresh the BGP routing table and apply a new routing policy
without breaking the NGP connections.
■ BGP soft reset requires all BGP routers in a network support the route-refresh
function. If there is a router not supporting the route-refresh function, you
need to configure the peer keep-all-routes command to save all the initial
routing information of peers for the use of BGP soft reset.
Configuring a
Large-Scale BGP
Network
In large-scale network, there are large quantities of peers. Configuring and
maintaining the peer becomes a big problem. Using peer group can ease the
management and improve the routes sending efficiency. According to the
different ASs where peers reside, the peer groups fall into IBGP peer groups and
EBGP peer groups. For the EBGP peer group, it can also be divided into pure EBGP
peer group and hybrid EBGP peer group according to whether the peers in the
EBGP group belong to the same exterior AS or not.
Configure the interval at which a peer
group sends the same route update
packet
peer group-name
route-update-interval
seconds
Optional
By default, the interval at
which a peer group sends
the same route update
packet to IBGP peers is 15
seconds, and to EBGP
peers is 30 seconds.
Configure the number of route
prefixes to be received from the BGP
peer/peer group
peer { group-name |
ip-address } route-limit
prefix-number [ [
alert-only | reconnect
reconnect-time ] |
percentage-value ] *
Optional
By default, there is no
limit on the number of
route prefixes to be
received from the BGP
peer/peer group.
Perform soft refreshment of BGP
connection manually
return -
refresh bgp { all |
ip-address | group
group-name } { export |
import }
Optional
system-view
Enter BGP view again
bgp as-number
Configure BGP to perform MD5
authentication when establishing TCP
connection
peer { group-name |
ip-address } password {
cipher | simple }
password
Optional
By default, BGP dose not
perform MD5
authentication when
establishing TCP
connection.
Configure the number of routes used
for BGP load balance
balance num
Optional
By default, the system
does not adopt BGP load
balance.
Table 283 Adjust and optimize a BGP network
Operation Command Description