7
Figure 5
Port link types
PVID
You can configure a port VLAN (PVID) for a port. By default, VLAN 1 is the PVID for all ports.
•
An access port can join only one VLAN. The VLAN to which the access port belongs is the PVID of
the port. The PVID of the access port changes along with the VLAN to which the port belongs.
•
A trunk or hybrid port can join multiple VLANs, and you can configure a PVID for the port.
•
You can use a nonexistent VLAN as the PVID for a hybrid or trunk port but not for an access port.
Therefore, after you remove the VLAN that an access port resides in with the
undo vlan
command,
the PVID of the port changes to VLAN 1. The removal of a VLAN specified as the PVID of a trunk or
hybrid port, however, does not affect the setting of the PVID on the port.
NOTE:
•
It is recommended that you set the same PVID for the local and remote ports.
•
Make sure that a port is assigned to its PVID. Otherwise, when receiving frames tagged with the PVID or
untagged frames (including protocol packets such as MSTP BPDUs), the port filters out these frames.
Ports of different link types handle frames as follows:
Port type
Actions (in the inbound direction)
Actions (in the outbound
direction)
Untagged frame
Tagged frame
Access
Tag the frame with the
PVID tag.
•
Receive the frame if its
VLAN ID is the same as the
PVID.
•
Drop the frame if its VLAN
ID is different from the
PVID.
Remove the VLAN tag and send
the frame.
