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One-Armed Single Network Mode
The WebMux supports
two kinds of “One-Armed” modes: Single Network Mode and Direct
Server Return (DSR) Mode. For Single Network Mode, there are no changes required for the
network topology or server IP addresses. Requests from
clients go to the farm address on the
WebMux, which will in turn go to the servers
through load balancing methods. The server
replies are directed back to the WebMux and sent back to the clients. Single Network Mode
has a 65,000 concurrent connections limit per farm.
One-Armed Single Network Mode (Installation without IP Address Change)
In Single Network Mode, connections being load balanced and going to the real servers will
appear to come from the WebMux itself. You will not need to make any changes on your
servers since the servers will always reply back to the WebMux when sending back their
reply.
You will only need to connect the “server LAN” side of the WebMux to the network.
Do not connect the “router LAN” side interfaces to your network.
Be aware that in this mode, the c
lient’s real IP addresses will not be logged in your server
log unless you modify your server’s logging filter rules. You have to make sure your server
logs the “X-Forwarded-For” (XFF) HTTP MIME header content to find the client’s real IP
address. If the HTTP header already has the X-Forwarded-For tag in it, the WebMux will not
alter the tag. If the traffic is not for the HTTP port, WebMux will not insert the XFF header for
the traffic. Enabling XFF header insertion is optional on
a per farm basis. If your host
software does not need this header, it is better not to insert it to reduce
the WebMux CPU
usage.
