H3C Technologies H3C S12500 Series Switches - Manual (Page 20)

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Figure 5 Network diagram
PVID
By default, VLAN 1 is the PVID for all ports. You can configure the PVID for a port as required.
Use the following guidelines when you configure the PVID on a port:
• 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.
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 the VLAN specified as the PVID of a trunk or hybrid
port, however, does not affect the PVID setting on the port.
• H3C recommends that you set the same PVID on local and remote ports.
• Make sure 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.
The following table shows how ports of different link types handle frames:
Port type
Actions (in the inbound direction)
Actions (in the outbound
direction)
Untagged frame Tagged frame
Access
Tag the frame with the
PVID.
• 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 PVID and send the
frame.