C
HAPTER
36
| VLAN Commands
Displaying VLAN Information
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interface, then that interface cannot be set to access mode, and vice
versa.
â—† To prevent loops from forming in the spanning tree, all unknown VLANs
will be bound to a single instance (either STP/RSTP or an MSTP
instance, depending on the selected STA mode).
â—† If both VLAN trunking and ingress filtering are disabled on an interface,
packets with unknown VLAN tags will still be allowed to enter this
interface and will be flooded to all other ports where VLAN trunking is
enabled. (In other words, VLAN trunking will still be effectively enabled
for the unknown VLAN).
EXAMPLE
The following example enables VLAN trunking on ports 9 and 10 to
establish a path across the switch for unknown VLAN groups:
Console(config)#interface ethernet 1/9
Console(config-if)#vlan-trunking
Console(config-if)#interface ethernet 1/10
Console(config-if)#vlan-trunking
Console(config-if)#
DISPLAYING VLAN INFORMATION
This section describes commands used to display VLAN information.
show vlan This command shows VLAN information.
SYNTAX
show vlan [id vlan-id | name vlan-name]
id - Keyword to be followed by the VLAN ID.
vlan-id - ID of the configured VLAN. (Range: 1-4094)
name - Keyword to be followed by the VLAN name.
vlan-name - ASCII string from 1 to 32 characters.
Table 137: Commands for Displaying VLAN Information
Command Function Mode
show interfaces status
vlan
Displays status for the specified VLAN interface NE, PE
show interfaces
switchport
Displays the administrative and operational status of
an interface
NE, PE
show vlan Shows VLAN information NE, PE