R0106-HP MSR Router Series Layer 3 - IP Routing Command Reference(V7)
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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
Predefined user roles
network-admin
Parameters
group-name: Specifies a peer group by its name, a case-sensitive string of 1 to 47 characters. The peer
group must have been created.
ip-address: Specifies a peer by its IP address. The peer must have been created.
ipv6-address: Specifies a peer by its IPv6 address. The peer must have been created.
Usage guidelines
BGP supports 4-byte AS numbers. The 4-byte AS number occupies four bytes, in the range of 1 to
4294967295. By default, a device sends an Open message to the peer device for session establishment.
The Open message indicates that the device supports 4-byte AS numbers. If the peer device supports
2-byte AS numbers instead of 4 -byte AS numbers, the session cannot be established. To resolve this issue,
enable the 4-byte AS number suppression function. The device then sends an Open message to inform
the peer that it does not support 4-byte AS numbers, so the BGP session can be established.
If the peer device supports 4-byte AS numbers, do not enable the 4-byte AS number suppression function.
Otherwise, the BGP session cannot be established.
Examples
# In BGP view, enable 4-byte AS number suppression for peer 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 suppress-4-byte-as
# In BGP-VPN instance view, enable 4-byte AS n u m b e r s u p p r e s s i o n f o r p e e r 1.1.1.1.
<Sysname> system-view
[Sysname] bgp 100
[Sysname-bgp] ip vpn-instance vpn1
[Sysname-bgp-vpn1] peer 1.1.1.1 as-number 200
[Sysname-bgp-vpn1] peer 1.1.1.1 capability-advertise suppress-4-byte-as
Related commands
display bgp peer