9-21
Cisco Systems IntelligentGigabit Ethernet Switch Modules for the IBM BladeCenter, Software Configuration Guide
24R9746
Chapter9 Configuring STP
Configuring Spanning-Tree Features
Configuring Spanning-Tree Timers
Table 9 -4 describes the timers that affect the en tire spanning-tree performance.
The sections that follow provide the configuration steps.

Configuring the Hello Time

You can configure the interval between the generation of configuration messages by the root switch by
changing the hello time.
Note Exercise care when using this command. For most situations, we recommend that you use the
spanning-tree vlan vlan-id root primary a nd the spanning-tree vlan vlan-id root secondary global
configuration commands to modify the hello time.
Beginning in privileged EXEC mode, follow these steps to configure the hello time of a VLAN. This
procedure is optional.
To return the switch to its default setting, use the no spanning-tree vlan vlan-id hello-time global
configuration command.
Table9-4 Spanning-Tree Timers
Variable Description
Hello timer Determines how often the switch broadcasts hello messages to other switches.
Forward-delay timer Determines how long each of the listening and learning states last before the interface begins
forwarding.
Maximum-age timer Determines the amount of time the switch stores protocol inform ation received on an interface.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 spanning-tree vlan vlan-id hello-time seconds Configure the hello time of a VLAN. The hello time is the
interval between the generation of configuration messages by
the root switch. These messages mean that the switch is alive.
•For vlan-id, you can specify a single VLAN identified by
VLAN ID number, a range of VLANs separated by a
hyphen, or a series of VLANs separated by a comma.
Valid interfaces include physical ports, VLANs, and port
channels. The range is 1 to 4094.
•For seconds, the range is 1 to 10; the default is 2.
Step3 end Return to privileged EXEC mode.
Step4 show spanning-tree vlan vlan-id Verify your entries.
Step5 copy running-config startup-config (Optional) Save your entries in the configuration file.