Configuring Spanning Tree Timers; Configuring The Hello Time - Cisco WS-X6066-SLB-APC - Content Switching Module Software Manual

Chapter 8 Configuring Spanning Tree
To prevent switches from becoming root, perform this task in privileged mode:
Task
Step 1
Enable root guard on a port.
Step 2
Verify that root guard is enabled.

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, or if you do not specify an MISTP instance when the
switch is in MISTP mode, MISTP instance 1 is assumed.
These sections describe how to configure spanning tree timers:
•
•
•
Exercise care using these commands. For most situations, we recommend that you use the set
Caution
spantree root and set spantree root secondary commands to modify the spanning tree performance
parameters.
Table 8-6
Table 8-6
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 of interval is 1 to 10 seconds.
78-13315-02
Configuring the Hello Time, page 8-35
Configuring the Forward Delay Time, page 8-36
Configuring the Maximum Aging Time, page 8-36
describes the switch variables that affect spanning tree performance.
Spanning Tree Timers
Description
Determines how often the switch broadcasts its hello message to
other switches.
Measures the age of the received protocol information recorded for
a port and ensures that this information is discarded when its age
limit exceeds the value of the maximum age parameter recorded by
the switch. The timeout value is the maximum age parameter of the
switches.
Monitors the time spent by a port in the learning and listening
states. The timeout value is the forward delay parameter of the
switches.
Command
set spantree guard {root | none} mod/port
show spantree guard {mod/port | vlan} {mistp-instance
instance | mod/port}
Catalyst 6000 Family Software Configuration Guide—Releases 6.3 and 6.4
Configuring Spanning Tree Timers
Default
2 seconds
20 seconds
15 seconds
8-35