Configuration Prerequisites; Tuning And Optimizing A Bgp Network - H3C S5600 Series Operation Manual

message from its peer in a specific period (know as Holdtime), the router considers the BGP connection
operates improperly and thus disconnects the BGP connection.
When establishing a BGP connection, the two routers negotiate for the Holdtime by comparing their
Holdtime values and take the smaller one as the Holdtime.
2) Limiting the number of route prefixes that can be learned from a peer/peer group
By limiting the number of route prefixes that can be learned from peer/peer group to reduce the size of
the local routing table, you can optimize the performance of the local router system and protect the local
router.
With this function enabled on a router, when the number of route prefixes learned from a peer/peer
group exceeds the configured value, the router automatically disconnects from the peer/peer group.
3) BGP connection reset
To make a new BGP routing policy taking effect, you need to reset the BGP connection. This temporarily
disconnects the BGP connection. The switches support the BGP route-refresh function. With
route-refresh function enabled on all the routers, if BGP routing policy changes, the local router sends
refresh messages to its peers. And the peers receiving the message in turn send their routing
information to the local router. Therefore, the local router can perform dynamic route update and apply
the new policy without tearing down BGP connections.
If a router not supporting route-refresh exists in the network, you can only reset BGP connections with
the refresh bgp command, resulting in temporary BGP disconnections.
4) BGP authentication
BGP uses TCP as the transport layer protocol. To improve the security of BGP connections, you can
specify to perform MD5 authentication when a TCP connection is established. Note that the MD5
authentication of BGP does not authenticate the BGP packets. It only configures the MD5
authentication password for TCP connection, and the authentication is performed by TCP. If
authentication fails, the TCP connection cannot be established.

Configuration Prerequisites

Before adjusting the BGP clock, enable basic BGP functions.
Before configuring BGP clock and authentication, make sure the following information is available.
Value of BGP timer
Interval for sending the update packets
MD5 authentication password

Tuning and Optimizing a BGP Network

Follow these steps to tune and optimize a BGP network:
Enter system view
Enter BGP view
Configure
BGP timer
To do...
Configure the Keepalive
time and Holdtime of
BGP.
Use the command...
system-view
bgp as-number
timer keepalive
keepalive-interval hold
holdtime-interval
5-23
Remarks
—
—
Optional
By default, the keepalive time is
60 seconds, and holdtime is 180