3Com Switch 8800 Configuration Guide
Chapter 6 Ethernet Port Configuration
6-8
By default, the VLAN of hybrid port and trunk port is VLAN 1 and that of the access port
is the VLAN to which it belongs
6.2.14 Setting the VLAN VPN Feature
VLAN Tag consists of 12 bits (defined by IEEE802.1Q), so Ethernet Switches can
support up to 4k VLANs. In networking, especially in MAN (metropolitan area network),
a large numbers of VLANs are required to segment users. In this case, 4k VLANs are
not enough.
VLAN VPN feature can provide duplex VLAN Tags to a packet, i.e. mark the packet with
another VLAN Tag besides the original one, thus to provide 4k x 4k VLANs to meet
user’s demands. At the same time, VLAN VPN feature provides the following functions:
using the original VLAN Tag to differentiate users and services, and using the new
VLAN Tag to load service and VPN users. These make VLAN configuration simple and
practicable. Thus, Ethernet Switches can meet the requirement of MAN.
If VLAN VPN is enabled on a port, all the packets (no matter whether it carries a VLAN
Tag or not) will be given a new Tag that specifies the default VLAN of this port.
Therefore, the packets that have had a VLAN Tag get two Tags, and the packets that
have not had a VLAN Tag get one.
Perform the following configuration in Ethernet port view.
Table 6-14
Set the VLAN VPN feature
Operation
Command
Enable the VLAN VPN feature
vlan-vpn
enable
Disable the VLAN VPN feature
undo
vlan-vpn
Note that if anyone of GVRP, STP, and 802.1x has been enabled on a port, VLAN VPN
cannot be enabled on it.
By default, the port VLAN VPN is disabled.
6.2.15 Copying Port Configuration to Other Ports
To keep the configuration of other ports consistent with a specified port, you can use
copy configuration
command to copy the configuration of that specified port to other
ports. Such configurations may involve: STP setting, QoS setting, LACP setting, and
port setting. The detailed table is as follows:
Table 6-15
Configurations that can be copied
Attribute
Detailed Setting
Enable/disable STP
STP setting
Port priority