Chapter 21
| VLAN Commands
Configuring Protocol-based VLANs
– 586 –
Command Mode
Privileged Exec
Example
Console#show vlan-translation
Interface Old VID New VID
--------- ------- -------
Eth 1/ 1 10 100
Console#
Configuring Protocol-based VLANs
The network devices required to support multiple protocols cannot be easily
grouped into a common VLAN. This may require non-standard devices to pass
traffic between different VLANs in order to encompass all the devices participating
in a specific protocol. This kind of configuration deprives users of the basic benefits
of VLANs, including security and easy accessibility.
To avoid these problems, you can configure this switch with protocol-based VLANs
that divide the physical network into logical VLAN groups for each required
protocol. When a frame is received at a port, its VLAN membership can then be
determined based on the protocol type in use by the inbound packets.
.
To configure protocol-based VLANs, follow these steps:
1. First configure VLAN groups for the protocols you want to use (page 563).
Although not mandatory, we suggest configuring a separate VLAN for each
major protocol running on your network. Do not add port members at this
time.
2. Create a protocol group for each of the protocols you want to assign to a VLAN
using the protocol-vlan protocol-group command (Global Configuration
mode).
Table 114: Protocol-based VLAN Commands
Command Function Mode
protocol-vlan protocol-
group
Create a protocol group, specifying the supported
protocols
GC
protocol-vlan protocol-
group
Maps a protocol group to a VLAN IC
show protocol-vlan
protocol-group
Shows the configuration of protocol groups PE
show interfaces protocol-
vlan protocol-group
Shows the interfaces mapped to a protocol group and the
corresponding VLAN
PE