NAME¶
fair —
simple TCP load balancing
service
DESCRIPTION¶
fair is a load balancer for TCP connections. It can be used to
distribute incoming connections for SMTP, HTTP or any other TCP service to
multiple hosts, distributing the load as evenly as possible.
fair consists of two daemons. The
carrousel
is the front-end; it keeps track of back-end hosts and their status, and
forwards incoming connections to the back-ends in such a way that the load is
distributed fairly. The
transponder runs on the back-end
hosts, it registers with the carrousel and sends it status information. The
TCP connections forwarded by the
carrousel are not sent to
the
transponder daemons but are sent directly to the desired
service running on the back-end host. Both daemons share a single
configuration file.
EXAMPLES¶
The following example shows how to set up
fair to service HTTP
connections and to distribute them over back-ends in the 192.168.1.0/24
subnet.
The configuration file
/etc/fair.conf contains the following:
WorkerService = http
BalancerService = http
AllowUDP = ^192.168.1.[0-9]+$
On
www.example.com, the front-end server receiving the
incoming HTTP connections, just run:
On each of the back-ends run:
transponder www.example.com
SEE ALSO¶
carrousel(8),
transponder(8),
fair.conf(5)
