LibreQoS

A simple way to shape hundreds of clients and reduce bufferbloat using fq_codel or CAKE. This is alpha software, please do not deploy in production.

Lab Requirements

• Edge and Core routers with MTU 1500 on links between them
• OSPF primary link (low cost) through the server running LibreQoS
• OSPF backup link recommended

Server Requirements

• VM or physical server
• One management network interface
• Two dedicated network interface cards, preferably SFP+ capable
• 8GB RAM or more recommended
• Python 3
• Recent Linux kernel
• tc (usually pre-installed)

Server Spec Recommendations

• For up to 1Gbps
  • 4+ CPU cores
  • 8GB RAM
  • 32GB Disk Space
  • Passmark score of 17,000 or more (AMD Ryzen 5 3600 or better)
• For up to 5Gbps
  • 8+ CPU cores
  • 16GB RAM
  • 32GB Disk Space
  • Passmark score of 23,000 or more (AMD Ryzen 7 3800X or better)
• For up to 10Gbps
  • 16+ CPU cores
  • 32GB RAM
  • 32GB Disk Space
  • Passmark score of 38,000 or more (AMD Ryzen 9 3950X or better) https://www.cpubenchmark.net/high_end_cpus.html

Features

• fq_codel
• Cake (Common Applications Kept Enhanced) [Experimental]
• HTB (Hierarchy Token Bucket)
• tc filters divided into groups with hashing filters to significantly increase efficiency

How to use

• Add linux interface bridge br0 to the two dedicated interfaces
  • For example on Ubuntu Server 20.04 which uses NetPlan, you would add the following to the .yaml file in /etc/netplan/

bridges:
    br0:
      interfaces:
           - eth4
           - eth5

• Modify setting parameters in LibreQoS.py to suit your environment
• Run:

sudo python3 ./LibreQoS.py

Special Thanks

Thank you to the hundreds of contributors to the cake and fq_codel projects. Thank you to Phil Sutter, Bert Hubert, Gregory Maxwell, Remco van Mook, Martijn van Oosterhout, Paul B Schroeder, and Jasper Spaans for contributing to the guides and documentation listed below.

References

• https://tldp.org/HOWTO/Adv-Routing-HOWTO/lartc.adv-filter.hashing.html
• http://linux-ip.net/gl/tc-filters/tc-filters.html

License

Copyright (C) 2020 Robert Chacón

LibreQoS is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 2 of the License, or (at your option) any later version.

LibreQoS is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with LibreQoS. If not, see http://www.gnu.org/licenses/.