Configuring The Maximum-Aging Time For A Vlan; Configuring Stp For Use In A Cascaded Stack - Cisco WS-C3550-12G Software Configuration Manual

Configuring Basic STP Features
To return the switch to its default setting, use the no spanning-tree vlan vlan-id forward-time global
configuration command.

Configuring the Maximum-Aging Time for a VLAN

Beginning in privileged EXEC mode, follow these steps to configure the STP maximum-aging time for
a VLAN:
Command
Step 1 configure terminal
Step 2
spanning-tree vlan vlan-id max-age seconds
Step 3 end
Step 4
show spanning-tree vlan vlan-id bridge [brief]
Step 5 copy running-config startup-config
To return the switch to its default setting, use the no spanning-tree vlan vlan-id max-age global
configuration command.

Configuring STP for Use in a Cascaded Stack

STP uses default values that can be reduced when configuring your switch in cascaded configurations.
If an STP root switch is part of a cluster that is one switch from a cascaded stack, you can customize
STP to reconverge more quickly after a switch failure.
stacks that use the GigaStack GBIC.
acceptable for these configurations.
Table 10-4 Default and Acceptable STP Parameter Settings (in seconds)
STP Parameter STP Default
Hello Time 2
Max Age 20
Forwarding Delay 15
Catalyst 3550 Multilayer Switch Software Configuration Guide
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Purpose
Enter global configuration mode.
Configure the maximum-aging time of a VLAN. The
maximum-aging time is the number of seconds a switch waits
without receiving STP configuration messages before
attempting a reconfiguration.
For vlan-id, the range is 1 to 1005. Do not enter leading
•
zeros.
For seconds, the range is 6 to 40 seconds; the default is 20
•
seconds.
Return to privileged EXEC mode.
Verify your entries.
(Optional) Save your entries in the configuration file.
Table 10-4 shows the default STP settings and those that are
Acceptable for Option 1 Acceptable for Option 2
1 1
6 10
4 7
Chapter 10
Figure 10-14 shows switches in three cascaded
Acceptable for Option 3
1
6
4
Configuring STP
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