R21xx-HP FlexFabric 11900 Layer 3 IP Routing Command Reference

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Usage guidelines
The route refresh function enables BGP to send and receive Route-refresh messages.
BGP uses the route refresh function to implement BGP session soft-reset. After a policy is modified, the
router advertises a Route-refresh message to the peers. The peers resend their routing information to the
router. After receiving the routing information, the router filters the routing information by using the new
policy. This method allows you to refresh the BGP routing table and apply the new route selection policy
without tearing down BGP sessions.
BGP route refresh requires that both the local router and the peer support route refresh.
If both the peer capability-advertise route-refresh and peer capability-advertise conventional
commands are executed, the last configuration takes effect.
Examples
# I n B G P v i ew, e n a b l e B G P r o u t e re f re s h f o r p e e r 1.1.1.1.
<Sysname> system-view
[Sysname] bgp 100
[Sysname-bgp] peer 1.1.1.1 as-number 100
[Sysname-bgp] peer 1.1.1.1 capability-advertise route-refresh
# In BGP-VPN instance view, enable BGP route refresh for peer 1::1.
<Sysname> system-view
[Sysname] bgp 100
[Sysname-bgp] ip vpn-instance vpn1
[Sysname-bgp-vpn1] peer 1::1 as-number 200
[Sysname-bgp-vpn1] peer 1::1 capability-advertise route-refresh
Related commands
• display bgp peer ipv4 unicast
• display bgp peer ipv6 unicast
• peer capability-advertise conventional
• peer keep-all-routes
• refresh bgp ipv4 unicast
• refresh bgp ipv6 unicast
peer capability-advertise suppress-4-byte-as
Use peer capability-advertise suppress-4-byte-as to enable 4-byte AS number suppression.
Use undo peer capability-advertise suppress-4-byte-as to disable the function.
Syntax
peer { group-name | ip-address | ipv6-address } capability-advertise suppress-4-byte-as
undo peer { group-name | ip-address | ipv6-address } capability-advertise suppress-4-byte-as
Default
The 4-byte AS number suppression function is disabled.
Views
BGP view, BGP-VPN instance view