18-9
Software Configuration Guide—Release 15.0(2)SG
OL-23818-01
Chapter 18 Configuring STP and MST Configuring STP
Designated bridge has priority 32768, address 00e0.4fac.b000
Designated port id is 128.2, designated path cost 19
Timers: message age 3, forward delay 0, hold 0
Number of transitions to forwarding state: 1
BPDU: sent 3, received 3417
Switch#
Enabling the Extended System ID
Note The extended system ID is enabled permanently on chassis that support 64 MAC addresses.
Use the spanning-tree extend system-id command to enable the extended system ID on chassis that
support 1024 MAC addresses. See the “Understanding the Bridge ID” section on page 18-2.
To enable the extended system ID, perform this task:
Note When you enable or disable the extended system ID, the bridge IDs of all active STP instances are
updated, which might change the spanning tree topology.
This example shows how to enable the extended system ID:
Switch# configure terminal
Switch(config)# spanning-tree extend system-id
Switch(config)# end
Switch#
This example shows how to verify the configuration:
Switch# show spanning-tree summary | include extended
Extended system ID is enabled.
Command Purpose
Step 1 Switch(config)# spanning-tree extend system-id Enables the extended system ID.
Disables the extended system ID.
Note You cannot disable the extended system ID on
chassis that support 64 MAC addresses or when
you have configured extended range VLANs (see
Table 18-4 on page 18-7).
Step 2 Switch(config)# end Exits configuration mode.
Step 3 Switch# show spanning-tree vlan vlan_ID Verifies the configuration.