CCNA Cisco Certified Network Associate Study Guide - FTP Server

600 Appendix B � Configuring the Catalyst 1900 Switch
Unfortunately, there is no command to clear more than one VLAN at a
time on the 1900. You would not typically clear more than a few VLANs
anyway because, functionally, it makes no difference if they are turned on.
If you had security, broadcast, or routing update issues, then you would need
to consider it.
Verifying Trunk Links
To verify your trunk ports, use the show trunk command. If you have more
than one port trunking and want to see statistics on only one trunk port, you
can use the show trunk [port_number] command.
For the 1900 switch, the FastEthernet port 0/26 is identified by trunk A,
and port 0/27 is identified by trunk B. Below, I demonstrate how to view the
trunk port on interface 26:
1900EN#sh trunk ?
A Trunk A
B Trunk B
1900EN#sh trunk a
DISL state: Auto, Trunking: On, Encapsulation type: ISL
Notice in this output that DISL is auto, trunking is on, and ISL is the
VLAN-encapsulation type on trunk links.
To see which VLANs are allowed on a trunked link, use the show trunk
[A or B] allowed-vlans command. The following example shows the
VLANs allowed on the trunked interface 26.
1900EN#sh trunk ?
A Trunk A
B Trunk B
1900EN#sh trunk a ?
allowed-vlans Display allowed vlans
joined-vlans Display joined vlans
joining-vlans Display joining vlans
prune-eligible Display pruning eligible vlans
1900EN#sh trunk a allowed-vlans
1-4, 6-1004
1900EN#