HP 6125G HP 6125G & 6125G/XG Blade Switches IP Multicast Configuration - Page 205

Configuring the NEXT_HOP attribute, Configuring the AS_PATH attributes

Page 205 highlights

Step 1. Enter system view. 2. Enter BGP view. 3. Enter IPv4 MBGP address family view. Command system-view bgp as-number ipv4-family multicast 4. Configure the default MED value. default med med-value 5. Enable the comparison of the MED of routes from different compare-different-as-med ASs. 6. Enable the comparison of the MED of routes from each AS. bestroute compare-med 7. Enable the comparison of the MED of routes from bestroute med-confederation confederation peers. Remarks N/A N/A N/A Optional. 0 by default. Optional. Not enabled by default. Optional. Not enabled by default. Optional. Not enabled by default. Configuring the NEXT_HOP attribute You can use the peer next-hop-local command to specify the local router as the next hop of routes sent to an MBGP IBGP peer or peer group. If load balancing is configured, the router specifies itself as the next hop of route advertisements to the multicast IBGP peer or peer group regardless of whether the peer next-hop-local command is configured. In a broadcast network where the local router has two multicast EBGP peers, the router does not specify itself as the next hop of routing information sent to the EBGP peers by default unless the peer next-hop-local command is configured. To specify the router as the next hop of routes sent to a peer or a peer group: Step 1. Enter system view. 2. Enter BGP view. 3. Enter IPv4 MBGP address family view. Command system-view bgp as-number ipv4-family multicast 4. Specify the router as the next hop of routes sent to a peer or peer { group-name | ip-address } a peer group. next-hop-local Remarks N/A N/A N/A Optional. By default, IPv6 MBGP specifies the local router as the next hop for routes sent to an EBGP peer or a peer group, but not for routes sent to an MBGP IBGP peer or a peer group. Configuring the AS_PATH attributes In general, MBGP checks whether the AS_PATH attribute of a route from a peer contains the local AS number. If it does, it discards the route to avoid routing loops. To configure the AS_PATH attributes: 194

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194
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.
Configure the default MED
value.
default med
med-value
Optional.
0 by default.
5.
Enable the comparison of the
MED of routes from different
ASs.
compare-different-as-med
Optional.
Not enabled by default.
6.
Enable the
comparison of the
MED of routes from each AS.
bestroute compare-med
Optional.
Not enabled by default.
7.
Enable the comparison of the
MED of routes from
confederation peers.
bestroute med-confederation
Optional.
Not enabled by default.
Configuring the NEXT_HOP attribute
You can use the
peer next-hop-local
command to specify the local router as the next hop of routes sent
to an MBGP IBGP peer or peer group. If load balancing is configured, the router specifies itself as the
next hop of route advertisements to the multicast IBGP peer or peer group regardless of whether the
peer
next-hop-local
command is configured.
In a broadcast network where the local router has two multicast EBGP peers, the router does not specify
itself as the next hop of routing information sent to the EBGP peers by default unless the
peer
next-hop-local
command is configured.
To specify the router as the next hop of routes sent to a peer or a peer group:
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.
Specify the router as the next
hop of routes sent to a peer or
a peer group.
peer
{
group-name
|
ip-address
}
next-hop-local
Optional.
By default, IPv6 MBGP specifies
the local router as the next hop for
routes sent to an EBGP peer or a
peer group, but not for routes sent
to an MBGP IBGP peer or a peer
group.
Configuring the AS_PATH attributes
In general, MBGP checks whether the AS_PATH attribute of a route from a peer contains the local AS
number. If it does, it discards the route to avoid routing loops.
To configure the AS_PATH attributes: