3Com Switch 8800 Family Configuration Guide

350 CHAPTER 32: INTEGRATED IS-IS CONFIGURATION
Configuring IS-IS Timers Setting the Hello packet broadcast interval
The IS-IS periodically sends the Hello packets from the interface and the routers
maintain the adjacency through the transmitting/receiving of the Hello packets
The Hello packet interval can be modified.
Perform the following configuration in interface view.
Usually, two types of Hello packets are transported over a broadcast link: Level-1
and Level-2 Hello packets. For different packets, different broadcast intervals
should be set. However, there are two exceptions. One is when there is no level
separation in the link, parameters of Level-1 and Level-2 need not be specified in
the command (adopt the default values). So the system will set the broadcast
intervals of all packets as that of the level-1 Hello packet. The other is if Hello
packets are not separated according to level-1 and level-2 on the p2p links, the
attribute of the packets need not be set either.
By default, Hello packets are transmitted on an interface every 10 seconds.
This command specifies to send Hello packets of the corresponding levels in the
Fast Hello mode (by setting the minimum value of Hello interval to 1 second). If
the number of packets is not specified in the related command, three Hello
packets will be sent per second.
Perform the following configuration in interface view.
If neither level-1 nor level-2 is specified, the default setting is Level-1 and Level-2
Hello interval. Namely, the command works on both Level-1 and Level-2.
Setting the CSNP packet broadcast interval
The CSNP packet is transmitted by the DIS over the broadcast network to
synchronize the link state database (LSDB). The CSNP packet is regularly broadcast
over the broadcast network at an interval, which can be set by users.
Perform the following configuration in interface view.
Tabl e 323 Set the Hello packet broadcast interval
Operation Command
Set Hello packet interval, measured in
seconds.
isis timer hello seconds [ level-1 | level-2 ]
Restore the default Hello packet interval on
the interface
undo isis timer hello [ level-1 | level-2 ]
Tabl e 324 Configure to send Hello packets of the corresponding levels in the Fast Hello
mode
Operation Command
Configure to send Hello packets of the
corresponding levels in the Fast Hello mode
isis timer hello minimal [ level-1 | level-2 ]
Restore the default value of Hello interval in
the Fast Hello mode.
undo isis timer hello minimal [ level-1 |
level-2 ]