Operation Manual – IPv6 Routing
H3C S3610&S5510 Series Ethernet Switches
Chapter 5 IPv6 BGP Configuration
5-15
To do...
Use the command...
Remarks
Configure to carry only the
public AS number in
updates sent to a
peer/peer group
peer
{
ipv6-group-name
|
ipv6-address
}
public-as-only
Optional
By default, BGP updates
carry private AS number
Substitute local AS
number for the AS
number of a peer/peer
group indicated in the
AS_PATH attribute
peer
{
ipv6-group-name
|
ipv6-address
}
substitute-as
Optional
Not substituted by default
5.6 Tuning and Optimizing IPv6 BGP Networks
This section describes configurations of IPv6 BGP timers, IPv6 BGP connection soft
reset and the maximum number of load balanced routes.
z
IPv6 BGP timers
After establishing an IPv6 BGP connection, two routers send keepalive messages
periodically to each other to keep the connection. If a router receives no keepalive
message from the peer after the holdtime elapses, it tears down the connection.
When establishing an IPv6 BGP connection, the two parties compare their holdtime
values, taking the shorter one as the common holdtime. If the holdtime is 0, neither
keepalive massage is sent, nor holdtime is checked.
z
IPv6 BGP connection soft reset
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 router not supporting route-refresh exists in the network, you need to configure the
peer keep-all-routes
command on the router to save all route updates, and then use
the
refresh bgp ipv6
command to soft-reset IPv6 BGP connections.
5.6.1 Prerequisites
Before configuring IPv6 BGP timers, you have:
z
Enabled IPv6 function
z
Configured IPv6 BGP basic functions