H3C Technologies H3C S7500E Series Switches - Manual (Page 222)

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MAC address in a MAC-to-VLAN mapping matches the source MAC address of the untagged
frame exactly, the device ends the search and adds a VLAN tag containing the corresponding
VLAN ID to the packet, the device ends the search and adds a VLAN tag containing the
corresponding VLAN ID to the packet. If not, the device continues to perform fuzzy matching,
searches the MAC-to-VLAN mappings whose masks are not all-Fs and performs a logical AND
operation on the search keyword and each mask. If the result of an AND operation matches the
corresponding MAC address exactly. If no match is found, the system looks up other types of
VLANs to make the forwarding decision.
When receiving a tagged frame, the receiving port forwards the frame if it is assigned to the
corresponding VLAN, or drops the frame if it is not. In this case, port-based VLAN applies.
Approach 2: Manually configuring static MAC-based VLANs and enabling ports to be
dynamically assigned to static MAC-based VLANs
After you configure a MAC-to-VLAN mapping, assign a port to the corresponding VLAN, and enable
MAC-based VLAN on the port, when the switch receives packets that match this MAC-to-VLAN
mapping from its other ports, it cannot assign these ports to the corresponding VLAN. Approach 2 can
solve this problem. In this approach, you must manually create MAC-to-VLAN mappings, enable
MAC-based VLAN, and enable MAC-based dynamic port assignment. After that, the device can
dynamically assign ports to static MAC-based VLANs based on the MAC addresses of received
packets.
When receiving an untagged frame, the device handles the frame and the receiving port as shown
in
Figure 1-1 .
Figure 1-1 Dynamically assign a port to a static MAC-based VLAN
Receive an untagged
frame
Any matched entry ?
No
Assign the receiving port to
the corresponding VLAN
有
Exact match ?
Yes
No
Search for matched MAC -to -
VLAN mapping according to
the source MAC of the frame
Forward the frame Drop the frame
Yes
When receiving a tagged frame, the receiving port forwards the frame if it is assigned to the
corresponding VLAN or drops the frame if it is not. In this case, port-based VLAN applies.