H3C Technologies H3C S10500 Series Switches - Manual (Page 246)

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Enabling logging of peer state changes
Follow these steps to enable the logging of peer state changes:
To do… Use the command… Remarks
Enter system view system-view —
Enter BGP view bgp as-number —
Enable the logging of peer state
changes globally
log-peer-change
Optional
Enabled by default
Enable the logging of peer state
changes for a peer or peer group peer { group-name | ip-address }
log-change Optional
Enabled by default
Configuring BFD for BGP
BGP maintains neighbor relationships based on the keepalive timer and holdtime timer, which are set in
seconds. BGP defines that the holdtime interval must be at least three times the keepalive interval. This
slows down link failure detection; once a failure occurs on a high-speed link, a large quantity of packets
will be dropped. BFD is introduced to solve this problem. It detects links between neighbors quickly to
reduce convergence time upon link failures.
Follow these steps to enable BFD for a BGP peer:
To do… Use the command… Remarks
Enter system view system-view —
Enter BGP view bgp as-number —
Enable BFD for the specified BGP
peer
peer ip-address bfd
Required
Not enabled for any BGP peer by
default
NOTE:
•
Before configuring BFD for BGP, you need to enable BGP.
• After a link failure occurs, BFD may detect the failure before the system performs GR. As a result, GR will
fail. If GR capability is enabled for BGP, use BFD with caution. If GR and BFD are both enabled, do not
disable BFD during a GR process; otherwise, GR may fail.
• For BFD configuration, see High Availability Configuration Guide.
Displaying and maintaining BGP
Displaying BGP
To do… Use the command… Remarks
Display peer group information
display bgp group [ group-name ] [ | { begin | exclude
| include } regular-expression ] Available in
any view