Configuring Spanning Tree Timers; Configuring The Hello Time - Cisco WS-C2948G-GE-TX Configuration Manual

Configuring Spanning Tree Timers

Configuring Spanning Tree Timers
Spanning tree timers affect the spanning tree performance. You can configure the spanning tree timers
for a VLAN in PVST+ or an MISTP instance in MISTP mode. If you do not specify a VLAN when the
switch is in PVST+ mode, VLAN 1 is assumed. If you do not specify an MISTP instance when the switch
is in MISTP mode, MISTP instance 1 is assumed.
Exercise care using these commands. For most situations, we recommend that you use the set spantree
Caution
root and set spantree root secondary commands to modify the spanning tree performance parameters.
Table 7-6
Table 7-6
Variable
Hello Time
Maximum Age
Timer
Forward Delay
Timer

Configuring the Hello Time

Enter the set spantree hello command to change the Hello time for a VLAN or for an MISTP instance.
The possible range for interval is from 1–10 seconds.
To configure the spanning tree bridge Hello time for a VLAN or an MISTP instance, perform this task
in privileged mode:
Task
Step 1
Configure the Hello time for a VLAN or
MISTP instance.
Step 2
Verify the configuration.
This example shows how to configure the spanning tree Hello time for VLAN 100 to 7 seconds:
Console> (enable) set spantree hello 7 100
Spantree 100 hello time set to 7 seconds.
Console> (enable)
This example shows how to set the spantree Hello time for an instance to 3 seconds:
Console> (enable) set spantree hello 3 mistp-instance 1
Spantree 1 hello time set to 3 seconds.
Console> (enable)
Catalyst 4500 Series, Catalyst 2948G, Catalyst 2948G-GE-TX, and Catalyst 2980G Switches Software Configuration Guide—Release 8.2GLX
7-44
describes the switch variables that affect spanning tree performance.
Switch Variable Descriptions
Description
Determines how often the switch broadcasts its Hello message to
other switches.
Measures the age of the received protocol information that is
recorded for a port and ensures that this information is discarded
when its age limit exceeds the value of the maximum age parameter
that is recorded by the switch. The timeout value is the maximum
age parameter of the switches.
Monitors the time that is spent by a port in the learning and
listening states. The timeout value is the forward delay parameter
of the switches.
Chapter 7
Command
set spantree hello interval [vlan] mistp-instance
[instances]
show spantree [vlan | mistp-instance instances]
Configuring Spanning Tree
Default
20 sec
2 sec
15 sec
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