Cisco Catalyst 2950 - Configuring the Maximum-Aging Time for a VLAN; Configuring STP for Use in a Cascaded Cluster

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Catalyst 2950 Desktop Switch Software Configuration Guide
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Chapter 9 Configuring STP
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:
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 Cluster
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. Figure 9-14 shows switches in three cascaded
clusters that use the GigaStack GBIC. Table 9-3 shows the default STP settings and those that are
acceptable for these configurations.
Step 4
show spanning-tree vlan vlan-id bridge [brief] Verify your entries.
Step 5
copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
spanning-tree vlan vlan-id max-age seconds 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 zeroes.
For seconds, the range is 6 to 40 seconds; the default is 20
seconds.
Step 3
end Return to privileged EXEC mode.
Step 4
show spanning-tree vlan vlan-id bridge [brief] Verify your entries.
Step 5
copy running-config startup-config (Optional) Save your entries in the configuration file.
Table 9-3 Default and Acceptable STP Parameter Settings (in seconds)
STP Parameter STP Default Acceptable for Option 1 Acceptable for Option 2 Acceptable for Option 3
Hello Time 2 1 1 1
Max Age 20 6 10 6
Forwarding Delay 15 4 7 4