H3C Technologies H3C S7500E Series Switches - Manual (Page 213)

15-5
To do… Use the command… Remarks
Bring up the VLAN interface undo shutdown
Optional
By default, a VLAN interface is in the up
state. In this case, the VLAN interface is
up so long as one port in the VLAN is up
and goes down if all ports in the VLAN
go down.
An administratively shut down VLAN
interface however will be in the down
state until you bring it up, regardless of
how the state of the ports in the VLAN
changes.
Before creating a VLAN interface for a VLAN, create the VLAN first.
Port-Based VLAN Configuration
Introduction to Port-Based VLAN
Port-based VLANs group VLAN members by port. A port forwards traffic for 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 three link types use
different VLAN tag handling methods. An access port belongs to only one VLAN and sends traffic
untagged. It is typically used to connect a terminal device unable to recognize VLAN
tagged-packets or when there is no need to separate different VLAN members. As shown in
Figure 15-4 , because Device A is connected with common PCs that cannot recognize VLAN
tagged-packets, you need to configure Device A’s ports that connect the PCs as access ports.
A trunk port can carry multiple VLANs to receive and send traffic for them. Except traffic of the
default VLAN, traffic sent through a trunk port will be VLAN tagged. Usually, ports connecting
network devices are configured as trunk ports. As shown in
Figure 15-4 , because Device A and
Device B need to transmit packets of VLAN 2 and VLAN 3, you need to configure the ports
interconnecting Device A and Device B as trunk ports and assign them to VLAN 2 and VLAN 3.
Like a trunk port, a hybrid port can carry multiple VLANs to receive and send traffic for them.
Unlike a trunk port, a hybrid port allows traffic of all VLANs to pass through VLAN untagged.
Usually, hybrid ports are configured to connect devices whose support for VLAN tagged-packets
you are uncertain about. As shown in
Figure 15-4 , Device B connects a small-sized LAN in which
some PCs belong to VLAN 2 while some other PCs belong to VLAN 3. In this case, you need to