User guide

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the corresponding IP addresses in the status screen. Although labels can be anything, it is
better to have meaningful and unique label for each farm. Since version 5.6, the label field is
also used as the host name in “HOST:” MIME header to when checking HTTP servers. The
“HOST:” MIME header is essential in virtual hosting as that will determine which site is
being accessed. The format of the farm label should be the site host name (i.e. www.xyz.com
),
max length 75 bytes. Without a label specified, a 401 (Unauthorized) error code is still
considered a live server. If you have a label specified and the server returns error code 401,
then the WebMux will consider that server dead. For both IIS and Apache servers doing
virtual hosting, the farm name label must be an existing web site name on the server. For
more information on Virtual hosting, please go to Appendix D for details.
In NAT mode, if you use the WebMux for your intranet, the farm IP address will be the
original IP address of the web or application server. The web or application server must have
its IP address in the address range of the Server LAN subnet. The WebMux will translate
farm IP address to the server IP address. You can use the IP address used as the Route LAN
IP of WebMux as your farm addresses to save an IP address. You can create more farms with
the same IP address, as long as the port number is different.
In the NAT mode, the WebMux also acts as a firewall. All ports except the farm port(s) are
blocked. All servers behind the WebMux will still be able to reach to the outside through the
WebMux. Traffic from the servers to the outside network will be seen as coming from the
WebMux’s Router LAN IP address, or proxy address. If a WebMux is placed behind a
firewall, be sure to allow the WebMux Router LAN IP address to get to anywhere/anyport.
All farm IP addresses should have rules to allow incoming traffic mapped to the address and
port number, as well as the return traffic for each farm IP address from any port to anywhere.
In Transparent Mode or Single Network Mode, there is no firewall protection from the
WebMux. All servers talk to each other freely across the WebMux. Load balancing occurs
when the farm IP is accessed.
In Out-of-Path Mode, only the Server LAN port is connected, and the farm(s) must use a
different IP address than the WebMux Server LAN IP address. You can use reuse an IP
address for more than one farm as long as the port number is different from each other. In this
mode, each server must add a loopback adapter. In a Windows server, the route for the
loopback adapter must be removed. Please refer to Appendix A and B for more detailed
procedures. The WebMux has been tested extensively working with all versions of Windows,
Linux and HP-UX 11.X under this mode. Other OS should also work fine.
CAUTION Once a new farm is added, the IP address of the farm cannot be changed. To
correct the IP address, the farm has to be deleted and a new one created.
Port Number:
This is the port number for the farm. If you are choosing one of the known services (see
below), you do not have to specify anything in this field. However, if the service you choose
is not listed in the list below, you will need to specify a port number here. For example, for
MS Terminal Services, use port number 3389. If you enable SSL termination (see “Enabling
SSL Termination” section), then specify port 80 for the farm and servers in the farm
(choosing “HTTP—hypertext transfer protocol will automatically specify port 80 for the
farm). The WebMux will terminate all SSL traffic on port 443 and send them to port 80(DO
NOT specify port 443 if you enable SSL termination).