3com S7906E 安装指导

 

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After modifying a route selection policy, you have to reset IPv6 BGP connections to make the new one 

take effect, causing a short time disconnection. The current IPv6 BGP implementation supports the 

route-refresh feature that enables dynamic IPv6 BGP routing table refresh without needing to 

disconnect IPv6 BGP links. 

With this feature enabled on all IPv6 BGP routers in a network, when a routing policy modified on a 

router, the router advertises a route-refresh message to its peers, which then send their routing 

information back to the router. Therefore, the local router can perform dynamic routing information 

update and apply the new policy without tearing down connections. 

If a peer not supporting route-refresh exists in the network, you need to configure the peer 

keep-all-routes command on the router to save all routes from the peer. When the routing policy is 

changed, the system will update the IPv6 BGP routing table and apply the new policy. 

Before configuring IPv6 BGP timers, you need to:  

z 

Enable IPv6 

z 

Configure IPv6 BGP basic functions 

Follow these steps to configure IPv6 BGP timers: 

Enter system view 

— 

Enter BGP view 

bgp as-number 

— 

Enter IPv6 address family view 

— 

Specify keepalive 
interval and holdtime 

timer keepalive keepalive 
hold holdtime 

Configure 
IPv6 BGP 
timers 

Configure keepalive 
interval and holdtime 
for an IPv6 peer/peer 
group 

peer { ipv6-group-name | 
ipv6-address } timer 
keepalive keepalive hold 
holdtime 

Optional 

The keepalive interval 
defaults to 60 seconds, 
holdtime defaults to 180 
seconds.  

Configure the interval for sending the 
same update to an IPv6 peer/peer 
group 

peer { ipv6-group-name | 
ipv6-address } 
route-update-interval 
interval 

Optional 

The interval for sending the 
same update to an iBGP peer 
or an eBGP peer defaults to 
15 seconds or 30 seconds 

 

z 

Timers configured using the timer command have lower priority than timers configured using the 

peer timer command. 

z 

The holdtime interval must be at least three times the keepalive interval.