HP 6125XLG R2306-HP 6125XLG Blade Switch Layer 3 - IP Routing Command Referenc - Page 289

peer default-route-advertise

Page 289 highlights

If a BGP router has multiple links to a peer, and the source interface fails, BGP has to reestablish TCP connections, causing network oscillation. To improve link availability, HP recommends that you use a loopback interface as the source interface. To establish multiple BGP sessions between two routers, specify the source interface for establishing TCP connections to each peer on the local router. Otherwise, the local BGP router might fail to establish TCP connections to a peer when using the outbound interface of the best route to the peer as the source interface. The source interfaces on the local router and the peer must be reachable. To specify an indirectly connected interface (except loopback interfaces) on an EBGP peer as the source interface, use the peer ebgp-max-hop command to allow the establishment of an EBGP session to the indirectly connected peer. If an interface has multiple IP addresses, use the primary IP address for establishing TCP connections. If an interface has multiple IPv6 addresses, select an IPv6 address as defined in RFC 3484 for establishing TCP connections. Examples # In BGP view, specify loopback 0 as the source interface for TCP connections to the peer group test. system-view [Sysname] bgp 100 [Sysname-bgp] peer test connect-interface loopback 0 # In BGP-VPN instance view, specify loopback 0 as the source interface for TCP connections to the peer group test. system-view [Sysname] bgp 100 [Sysname-bgp] ip vpn-instance vpn1 [Sysname-bgp-vpn1] peer test connect-interface loopback 0 Related commands peer ebgp-max-hop peer default-route-advertise Use peer default-route-advertise to advertise a default route to a peer or peer group. Use undo peer default-route-advertise to disable default route advertisement to a peer or peer group. Syntax In BGP IPv4 unicast instance view/BGP-VPN IPv4 unicast instance view: peer { group-name | ip-address } default-route-advertise [ route-policy route-policy-name ] undo peer { group-name | ip-address } default-route-advertise [ route-policy route-policy-name ] In BGP IPv6 unicast instance view: peer { group-name | ipv6-address } default-route-advertise [ route-policy route-policy-name ] undo peer { group-name | ipv6-address } default-route-advertise [ route-policy route-policy-name ] Default No default route is advertised to a peer or peer group. 278

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278
If a BGP router has multiple links to a peer, and the source interface fails, BGP has to reestablish TCP
connections, causing network oscillation. To improve link availability, HP recommends that you use a
loopback interface as the source interface.
To establish multiple BGP sessions between two routers, specify the source interface for establishing TCP
connections to each peer on the local router. Otherwise, the local BGP router might fail to establish TCP
connections to a peer when using the outbound interface of the best route to the peer as the source
interface.
The source interfaces on the local router and the peer must be reachable.
To specify an indirectly connected interface (except loopback interfaces) on an EBGP peer as the source
interface, use the
peer
ebgp-max-hop
command to allow the establishment of an EBGP session to the
indirectly connected peer.
If an interface has multiple IP addresses, use the primary IP address for establishing TCP connections. If
an interface has multiple IPv6 addresses, select an IPv6 address as defined in RFC 3484 for establishing
TCP connections.
Examples
# In BGP view, specify loopback 0 as the source interface for TCP connections to the peer group
test
.
<Sysname> system-view
[Sysname] bgp 100
[Sysname-bgp] peer test connect-interface loopback 0
# In BGP-VPN instance view, specify loopback 0 as the source interface for TCP connections to the peer
group
test
.
<Sysname> system-view
[Sysname] bgp 100
[Sysname-bgp] ip vpn-instance vpn1
[Sysname-bgp-vpn1] peer test connect-interface loopback 0
Related commands
peer ebgp-max-hop
peer default-route-advertise
Use
peer default-route-advertise
to advertise a default route to a peer or peer group.
Use
undo peer default-route-advertise
to disable default route advertisement to a peer or peer group.
Syntax
In BGP IPv4 unicast instance view/BGP-VPN IPv4 unicast instance view:
peer
{
group-name
|
ip-address
}
default-route-advertise
[
route-policy
route-policy-name
]
undo peer
{
group-name
|
ip-address
}
default-route-advertise
[
route-policy
route-policy-name
]
In BGP IPv6 unicast instance view:
peer
{
group-name
|
ipv6-address
}
default-route-advertise
[
route-policy
route-policy-name
]
undo peer
{
group-name
|
ipv6-address
}
default-route-advertise
[
route-policy
route-policy-name
]
Default
No default route is advertised to a peer or peer group.