114
Tagged Ports:
Ethernet1/0/3
Untagged Ports:
Ethernet1/0/2
Configuring MAC-based VLANs
Introduction to MAC-based VLAN
The MAC-based VLAN feature assigns hosts to a VLAN based on their MAC addresses. This feature
is usually used in conjunction with security technologies such as 802.1X to provide secure, flexible
network access for terminal devices.
Static MAC-based VLAN assignment
Static MAC-based VLAN assignment applies to networks containing a small number of VLAN users.
In such a network, you can create a MAC address-to-VLAN map containing multiple MAC
address-to-VLAN entries on a port, enable the MAC-based VLAN feature on the port, and assign the
port to MAC-based VLANs.
With static MAC-based VLAN assignment configured on a port, the device processes received
frames by using the following guidelines:
•
When the port receives an untagged frame, the device looks up the MAC address-to-VLAN
map based on the source MAC address of the frame for a match.
a.
If the MAC address of a MAC address-to-VLAN entry matches the source MAC address of
the untagged frame, the device tags the frame with the corresponding VLAN ID and
forwards the frame.
b.
If no match is found, the device assigns a VLAN to the frame by using other criteria, such as
protocol, and forwards the frame.
c.
If no VLAN is available, the device tags the frame with the PVID of the receiving port and
forwards the frame.
•
When the port receives a tagged frame, the port forwards the frame if the VLAN ID of the frame
is permitted by the port, or otherwise drops the frame.
Dynamic MAC-based VLAN
You can use dynamic MAC-based VLAN with access authentication (such as 802.1X authentication
based on MAC addresses) to implement secure, flexible terminal access. After configuring dynamic
MAC-based VLAN on the device, you must configure the username-to-VLAN entries on the access
authentication server.
When a user passes authentication of the access authentication server, the device obtains VLAN
information from the server, generates a MAC address-to-VLAN entry by using the source MAC
address of the user packet and the VLAN information, and assigns the port to the MAC-based VLAN.
When the user goes offline, the device automatically deletes the MAC address-to-VLAN entry, and
removes the port from the MAC-based VLAN. For more information about 802.1X, MAC, and portal
authentication, see
Security Configuration Guide
.
Configuration restrictions and guidelines
When you configure a MAC-based VLAN, follow these guidelines:
•
MAC-based VLANs are available only on hybrid ports.
•
The MAC-based VLAN feature is mainly configured on the downlink ports of the user access
devices. Do not enable this function together with link aggregation.