Chapter 51: MAC Address-based VLANs
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VLAN Hierarchy The switch employs a VLAN hierarchy when handling untagged packets
that arrive on a port that is an egress port of a MAC address-based VLAN
as well as an untagged port of a port-based VLAN. (A port can be a
member of both types of VLANs at the same time.) The rule is that a MAC
address-based VLAN takes precedence over that of a port-based VLAN.
When an untagged packet arrives on a port, the switch first compares the
source MAC address of the packet against the MAC addresses of all the
MAC address-based VLANs on the device. If there is a match, the switch
considers the packet as a member of the corresponding MAC address-
based VLAN and not the port-based VLAN, and forwards it out the egress
ports defined for the corresponding MAC address-based VLAN.
If there is no match, the switch considers the packet as a member of the
port-based VLAN and forwards the packet according to the PVID assigned
to the port. For an explanation of a PVID, refer to “Port-based VLAN
Overview” on page 690.
Table 76. Example of a MAC Address-based VLAN Spanning Switches
Switch A Switch B
VLAN Name: Sales VLAN Name: Sales
MAC Address Egress Ports MAC Address Egress Ports
Address_1 1,3,4,5 Address_1 11,12,14,16
Address_2 1 Address_2 11
Address_3 1 Address_3 11
Address_4 1 Address_4 11
Address_5 1 Address_5 11
Address_6 1 Address_6 11