141Step Command Remarks6. Configure the MTU for theVLAN interface. mtu size The default setting is 1500 bytes.7. Configure the expectedbandwidth of the interface. bandwidth bandwidth-valueBy default, the expected bandwidth (inkbps) is the interface baud rate dividedby 1000.8. (Optional.) Restore thedefault settings for theVLAN interface.default N/A9. (Optional.) Cancel theaction of manually shuttingdown the VLAN interface.undo shutdownBy default, a VLAN interface is notmanually shut down. The VLAN interfaceis up if one or more ports in the VLAN isup, and goes down if all ports in theVLAN go down.Configuring port-based VLANsIntroduction to port-based VLANPort-based VLANs group VLAN members by port. A port forwards packets from a VLAN only after it isassigned to the VLAN.Port link typeYou can configure the link type of a port as access, trunk, or hybrid. The link types use the followingVLAN tag handling methods:• Access—An access port can forward packets from only one VLAN and send these packetsuntagged. An access port can connect a terminal device that does not support VLAN packets or isused in scenarios that do not distinguish VLANs.• Trunk—A trunk port can forward packets from multiple VLANs. Except packets from the port VLANID (PVID), packets sent out of a trunk port are VLAN-tagged. Ports connecting network devices aretypically configured as trunk ports.• Hybrid—A hybrid port can forward packets from multiple VLANs. A hybrid port allows traffic fromsome VLANs to pass through untagged and traffic from other VLANs to pass through tagged.Hybrid ports are typically used in one-to-two VLAN mapping to remove SVLAN tags beforeforwarding packets from multiple service provider VLANs to the customer network. For moreinformation about one-to-two VLAN mapping, see "Configuring VLAN mapping."PVIDThe PVID identifies the default VLAN of a port.When you configure 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 ofthe port.• A trunk or hybrid port can carry multiple VLANs, and you can configure a PVID for the port.• When you use the undo vlan command to delete the PVID of a port, the following conditions occurdepending on the port link type:{ For an access port, the PVID of the port changes to VLAN 1.
