H3C Technologies H3C S12500 Series Switches - Manual (Page 244)

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The current MBGP implementation supports the route-refresh feature that enables dynamic route refresh
without terminating MBGP connections.
However, if a peer not supporting route-refresh exists in the network, you need to configure the peer
keep-all-routes command to save all routes from the peer. When the routing policy is changed, the
system will update the MBGP routing table and apply the new policy.
Performing soft reset through route-refresh
If the peer is enabled with route-refresh, when the MBGP route selection policy is modified on a switch,
the switch advertises a route-refresh message to its MBGP peers, which resend their routing information
to the switch after receiving the message. Therefore, the local switch can perform dynamic route update
and apply the new policy without terminating MBGP connections.
To configure MBGP soft reset through route-refresh:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter BGP view. bgp as-number N/A
3. Enable BGP route refresh for a
peer/peer group.
peer { group-name | ip-address }
capability-advertise route-refresh Optional.
Enabled by default.
Performing a manual soft reset
If the peer does not support route-refresh, you can use the peer keep-all-routes command to save all the
route updates from the peer, and then use the refresh bgp ipv4 multicast command to soft-reset MBGP
connections to refresh the MBGP routing table and apply the new policy without terminating MBGP
connections.
To configure MBGP manual soft reset
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter BGP view. bgp as-number N/A
3. Disable BGP route-refresh and
multi-protocol extensions for a
peer/peer group.
peer { group-name | ip-address }
capability-advertise conventional Optional.
Enabled by default.
4. Enter IPv4 MBGP address
family view.
ipv4-family multicast N/A
5. Keep all original routes from a
peer/peer group regardless
of whether they pass the
inbound filtering policies.
peer { group-name | ip-address }
keep-all-routes
Not kept by default.
6. Return to user view. return N/A
7. Soft-reset MBGP connections
manually.
refresh bgp ipv4 multicast { all |
ip-address | group group-name |
external | internal } { export |
import }
Optional.