Python Load Balancer (Based on PumpkinLB project)

Intro

Changing the LoadBalancer's Destination-Decision Algorithm during the run time without the needs of reloading the LoadBalancer itself and preventing the packet loss is considered as a major hindrance in the IT field. Knowing that, I have re-developed a Free OpenSource LoadBalancer called PumpkinLB and added a web server to it. By doing so, a new config file(new sets of destinations) as JSON format can be sent to the LoadBalancer as an Http post request in order to dynamically change the LoadBalancing algorithm.

Requirement

• Python 3.7 (ONLY :D)

How To RUN

Run the code below

python3.7 PumpkinLB.py example.cfg

Initial Configuration and Config File

To run this LoadBalancer a config file is needed. It is recommended that read more about this config file format here https://github.com/kata198/PumpkinLB

How It Works

During the LoadBalancer's start-time, separate processes are created for each listener (listeners are defined in the config file). Each listener process, moreover, creates sub-processes(request handler worker) to route the packet to the specific destination.

=========

LoadBalancing Algorithm

=========

Examples JSON Post Requests

The HTTP server for this LoadBalancer has been configured to run on port 9090

• Change LoadBalancing algorithm to Round Robin

  {
  "servers":[ {"addr":"192.168.1.2", "port":8000}, {"addr":"192.168.1.3", "port":8000}]
  } 
  

• Change LoadBalancing algorithm to Weighted (2 to 1)

  {
  "servers":[ {"addr":"192.168.1.2", "port":8000}, {"addr":"192.168.1.2", "port":8000}, {"addr":"192.168.1.3", "port":8000}]
  } 
  

• Change LoadBalancing algorithm to Weighted (3 to 2)

  {
  "servers":[ {"addr":"192.168.1.2", "port":8000}, {"addr":"192.168.1.2", "port":8000}, {"addr":"192.168.1.2", "port":8000}, {"addr":"192.168.1.3", "port":8000}, {"addr":"192.168.1.3", "port":8000}]
  } 
  

• Add new destination(192.168.1.4) to current destinations (current destinations are: "192.168.1.2" and "192.168.1.3") and the current LoadBalancing algorithm is Round Robin

  {
  "servers":[ {"addr":"192.168.1.2", "port":8000}, {"addr":"192.168.1.3", "port":8000}, {"addr":"192.168.1.4", "port":8000}]
  }