Cisco 300 Series

Virtual Local Area Network (VLAN) Commands
1089 OL-32830-01 Command Line Interface Reference Guide
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User Guidelines
The switch requires an internal VLAN in the following cases:
• One VLAN for each IP interface is defined directly on an Ethernet port or on
a Port channel.
• One VLAN for each IPv6 tunnel.
• One VLAN for 802.1x.
When a switch needs an internal VLAN it takes a free VLAN with the highest VLAN
ID.
Use the vlan prohibit-internal-usage command to define a list of VLANs that cannot
be used as internal VLANs after reload.
If a VLAN was chosen by the software for internal usage, but you want to use that
VLAN for a static or dynamic VLAN, do one of the following
• Add the VLAN to the Prohibited User Reserved VLAN list.
• Copy the Running Configuration file to the Startup Configuration file
• Reload the switch
• Create the VLAN
Examples
Example 1—The following example specifies that VLANs 4010, 4012, and
4090-4094 cannot be used as internal VLANs:
vlan prohibit-internal-usage add 4010,4012,4090-4094
Example 2—The following specifies that all VLANs except 4000-4107 cannot be
used as internal VLANs:
vlan prohibit-internal-usage all
vlan prohibit-internal-usage remove 4000-4107
Example 3—The following specifies that all VLANs except 4000-4107 cannot be
used as internal VLANs: