H3C Technologies H3C S5560 Series Switches - Manual (Page 157)

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Step Command Remarks
9. (Optional.) Bring up the
VLAN interface.
undo shutdown
By default, a VLAN interface is not
manually shut down. The VLAN interface
is up if one or more ports in the VLAN is
up, and goes down if all ports in the
VLAN go down.
Configuring port-based VLANs
Introduction
Port-based VLANs group VLAN members by port. A port forwards packets from a VLAN only after it is
assigned to the VLAN.
Port link type
You can configure the link type of a port as access, trunk, or hybrid. The link types use the following
VLAN tag handling methods:
• Access—An access port can forward packets from only one VLAN and send these packets
untagged. An access port can connect a terminal device that does not support VLAN packets or is
used in scenarios that do not distinguish VLANs.
• Trunk—A trunk port can forward packets from multiple VLANs. Except packets from the port VLAN
ID (PVID), packets sent out of a trunk port are VLAN-tagged. Ports connecting network devices are
typically configured as trunk ports.
• Hybrid—A hybrid port can forward packets from multiple VLANs. The tagging status of the packets
forwarded by a hybrid port depends on the port configuration. Hybrid ports are typically used in
one-to-two VLAN mapping to remove SVLAN tags for downlink traffic. For more information about
one-to-two VLAN mapping, see "Configuring VLAN mapping."
PVID
The PVID identifies the default VLAN of a port.
When configuring the PVID on a port, follow these restrictions and guidelines:
• An access port can join only one VLAN. The VLAN to which the access port belongs is the PVID of
the port.
• A trunk or hybrid port supports multiple VLANs and the PVID configuration.
• When you use the undo vlan command to delete the PVID of a port, either of the following events
occurs depending on the port link type:
{
For an access port, the PVID of the port changes to VLAN 1.
{
For a hybrid or trunk port, the PVID setting on the port does not change.
You can use a nonexistent VLAN as the PVID for a hybrid or trunk port, but not for an access port.
• H3C recommends that you set the same PVID for a local port and its peer.
• To prevent a port from dropping packets from its PVID and untagged packets, assign the port to its
PVID.