HP 6125G HP 6125G & 6125G/XG Blade Switches IP Multicast Configuration - Page 206

Tuning and optimizing MBGP networks, Configuring MBGP soft reset

Page 206 highlights

Step Command 1. Enter system view. system-view 2. Enter BGP view. bgp as-number 3. Enter IPv4 MBGP address family view. ipv4-family multicast 4. Allow the local AS number to appear in the AS_PATH of routes from a peer or a peer group and specify the number peer { group-name | ip-address } of times that the local AS allow-as-loop [ number ] number can appear in the AS_PATH of routes from the peer or the peer group. 5. Disable BGP from considering the AS_PATH during best bestroute as-path-neglect route selection. 6. Configure updates to a peer or a peer group not to keep private AS numbers. peer { group-name | ip-address } public-as-only Remarks N/A N/A N/A Optional. By default, the local AS number cannot appear in routes from a peer or a peer group. Optional. By default, BGP considers AS_PATH during best route selection. Optional. By default, BGP updates carry private AS numbers. Tuning and optimizing MBGP networks This task involves resetting MBGP connections and configuring load balancing. Before configuring this task, configure basic MBGP functions first. Configuring MBGP soft reset After modifying a route selection policy, you have to reset MBGP connections to make it take effect. The current MBGP implementation supports the route refresh feature that enables dynamic route refresh without terminating MBGP connections. However, if a peer that does not support route refresh exists in the network, you must configure the peer keep-all-routes command to save all routes from the peer. When the routing policy is changed, the system updates the MBGP routing table and applies 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 router, the router advertises a route-refresh message to its MBGP peers, which resend their routing information to the router after receiving the message. Therefore, the local router can perform dynamic route update and apply the new policy without terminating MBGP connections. To perform soft reset through route refresh: Step 1. Enter system view. 2. Enter BGP view. Command system-view bgp as-number Remarks N/A N/A 195

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195
Step
Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enter BGP view.
bgp
as-number
N/A
3.
Enter IPv4 MBGP address
family view.
ipv4-family multicast
N/A
4.
Allow the local AS number to
appear in the AS_PATH of
routes from a peer or a peer
group and specify the number
of times that the local AS
number can appear in the
AS_PATH of routes from the
peer or the peer group.
peer
{
group-name
|
ip-address
}
allow-as-loop
[
number
]
Optional.
By default, the local AS number
cannot appear in routes from a
peer or a peer group.
5.
Disable BGP from considering
the AS_PATH during best
route selection.
bestroute as-path-neglect
Optional.
By default, BGP considers
AS_PATH during best route
selection.
6.
Configure updates to a peer
or a peer group not to keep
private AS numbers.
peer
{
group-name
|
ip-address
}
public-as-only
Optional.
By default, BGP updates carry
private AS numbers.
Tuning and optimizing MBGP networks
This task involves resetting MBGP connections and configuring load balancing.
Before configuring this task, configure basic MBGP functions first.
Configuring MBGP soft reset
After modifying a route selection policy, you have to reset MBGP connections to make it take effect.
The current MBGP implementation supports the route refresh feature that enables dynamic route refresh
without terminating MBGP connections.
However, if a peer that does not support route refresh exists in the network, you must configure the
peer
keep-all-routes
command to save all routes from the peer. When the routing policy is changed, the
system updates the MBGP routing table and applies 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 router,
the router advertises a route-refresh message to its MBGP peers, which resend their routing information
to the router after receiving the message. Therefore, the local router can perform dynamic route update
and apply the new policy without terminating MBGP connections.
To perform 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