A small TCP load balancer written in Go based on:

https://github.com/lumanetworks/go-tcp-proxy

This load balancer is NOT made for balancing many connections (for instance hundreds or thousands a second) but is meant for relatively few connections like SSH connections which create a lot of load (because the users start tasks).

Where I worked, this program was used for "all purpose" compute servers to run MATLAB jobs or run some compiled C code. It is in use at a University to distribute clients to the server with the lowest load.

If you move this project to some other location in the file system you must update the init scripts so they start properly.

The PWD of the process needs to be in the same dir as the PHP script!

The load balancer knows two strategies to forward clients.

For this to work you need nrpe client installed. nrpe is the client used by nagios.

The load balancer then runs the nrpe command check_load which must be configured like this in nrpe.cfg:

command[check_load]=/usr/lib64/nagios/plugins/check_load -w 15,10,5 -c 30,25,20 

This will return the one minute load and forward the client to the server that still has the most load free.

Ie, given:

• 24 core machine and load 15
• 12 core machine and load 8

the algorithm would still choose the 24 core machine even though it has a higher load. This is because the server has still more resources available than the 12 core server.

RAM is not taken into account but it would not be difficult to do so.

If no server has load information then round robin strategy kicks in.

Upstart scripts are in scripts subdirectory.

Copyright © 2014 Andre Rauh rauh@udel.edu

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

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