User guide

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Appendix J
Tagged VLAN and WebMux
VLANs may be untagged and tagged. To use untagged VLANs, also known as port based
VLANs, no additional configuration of the WebMux is necessary.
To the WebMux it appears as if no VLANs are used, and VLAN configuration is done on the
switches. This appendix will discuss using tagged VLANs, also known as 802.1q VLANs for
the original networks configured on the WebMux.
When you configure the WebMux original network addresses and masks, whether with the
front keypad and LCD (see Initial Configuration, page 25), the browser screen (see Initial
Setup Change through Browser, page 84), or through the superuser’s command line interface
with rec_cmdline (see Appendix F), you may also specify VLAN tagging for these networks.
VLAN tagging is optional. If it is used, the switches to which the WebMux is connected must
also be configured correctly to use these tags. (When additional networks are configured for
the WebMux using the superuser’s command line utility nwconfig, you may also arrange for
their VLAN tagging at that time. See Appendix L.)
Besides configuring the WebMux to use VLAN tags, the switches to which the WebMux is
connected must be configured to use these tags. In most switches, there are three items to be
addressed when setting up VLANs: the VLAN name, the port participation, and if it will be
tagged or untagged.
First a VLAN must be chosen and named. Choosing a VLAN name on the switch does not
automatically determine whether its VLAN is tagged or untagged. It merely specifies its
name.
Once the VLAN name has been chosen, you must next select which ports participate in this
VLAN. If the port selection does not match the physical connectivity, traffic will not pass.
The third and very important setting to make sure is that the port on the switch connected to
the WebMux will accept correctly tagged VLAN packets only. In some switches, you must
first configure the port to use .general. mode and then specify that the port will be tagged. If
you plan to use more than one VLANs, you may configure the switch port to be trunk port, or
add multiple VLAN tags to it.
At this point you should be able to access the WebMux from other devices that are also using
the same tagged VLAN ID.
There are some specific considerations when configuring VLAN IDs in NAT, Transparent, or
Out-of-Path Mode. In NAT mode, you have the option to have a VLAN ID for both the
Router (Internet) LAN interface and the Server LAN interface. Even though the WebMux
will allow for both sides to have the same VLAN ID, it is still recommended that you have a
different VLAN ID for each to ensure complete network separation between both sides.
In Transparent mode, you will only have one Bridge IP address, but you will need to create a
VLAN ID on both the Router (Internet) LAN interface and the Server LAN interface. The
WebMux will allow you to create the same VLAN ID on both interfaces, but this is not
recommended, unless each physical side is on a separate switch completely isolated from
each other. Be careful of Ethernet Bridge loops.