F3215-HP Load Balancing Module Network Management Configuration Guide-6PW101

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Enabling 4-byte AS number suppression
When a device that supports 4-byte AS numbers sends an Open message for session establishment, the
Optional parameters field of the message indicates that the AS number occupies four bytes—in the
range of 1 to 4294967295. If the peer device does not support 4-byte AS numbers (for examples, it
supports only 2-byte AS numbers), the session cannot be established.
After you enable the 4-byte AS number suppression function, the peer device can then process the Open
message even though it does not support 4-byte AS numbers, and 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 peer relationship cannot be established.
To enable 4-byte AS number suppression:
Ste
p
Command Remarks
1. Enter system view.
system-view N/A
2. Enter BGP view.
bgp as-number N/A
3. Enable 4-byte AS number
suppression.
peer { group-name | ip-address }
capability-advertise
suppress-4-byte-as
Disabled by default.
Enabling quick reestablishment of direct EBGP session
When the link to a directly connected EBGP peer is down, the router, with quick EBGP session
reestablishment enabled, tears down the session to the peer, and then reestablishes a session
immediately. If the function is not enabled, the router does not tear down the session until the holdtime
times out. A route flap does not affect the EBGP session state when the quick EBGP session
reestablishment is disabled.
To enable quick reestablishment of direct EBGP session:
Ste
p
Command Remarks
1. Enter system view.
system-view
N/A
2. Enter BGP view.
bgp as-number N/A
3. Enable quick reestablishment
of direct EBGP session.
ebgp-interface-sensitive
Optional.
Not enabled by default.
Enabling MD5 authentication for BGP peers
You can enable MD5 authentication to enhance security in the following ways:
• Perform MD5 authentication when establishing TCP connections. Only the two parties that have the
same password configured can establish TCP connections.
• Perform MD5 calculation on TCP packets to avoid modification to the encapsulated BGP packets.
To enable MD5 authentication for BGP peers:
Ste
p
Command Remarks
1. Enter system view.
system-view N/A
2. Enter BGP view. bgp as-number N/A