CAKE QoS Script (OpenWrt)

This is the script that I made months ago (to self-learning) and until today I have time to share it.

Quick Overview

1. The script launches the CAKE qdisc (like SQM would do), and you do not need SQM at all.
2. The script uses the veth method on the ingress side to make the DSCP marking work and fix this problem:

With dual-dsthost enabled, a single host with many tcp sessions (like when torrenting) is prevented from hogging all the bandwidth, but if you are actually using that host, the torrent will still hog that host's bandwidth and to fix that problem you need QoS using DSCP marking, so that the torrent traffic and other such hogs goes into the "bulk class", then that host will see a big improvement in all other traffic types.

3. It has rules to prioritize non-bulk unmarked traffic like gaming and VoIP, that means you don't need to add game ports, but if you want you can also add game ports and static IP of game consoles to prioritize that traffic (although it is not necessary).
4. It has rules to give high priority to known Video conferencing, VoIP and VoWiFi ports.
5. Easily change the default OpenWrt settings like default qdisc, TCP congestion control and ECN.
6. irqbalance and Packet Steering options to equally distribute the load of packet processing over all available cores and probably increase performance.
7. It has Init Script so that from the LuCI web interface (System -> Startup) you can Enable, Disable, Start, Restart and Stop the script.
8. It has Hotplug to automatically reload the script.

Pre-requisites

To use this script, you need to install these packages:

• tc-tiny
• kmod-sched-cake
• kmod-veth
• kmod-tcp-bbr
• irqbalance
• htop (Optional)

Copy and paste this into your SSH client:

opkg update && opkg install tc-tiny kmod-sched-cake kmod-veth kmod-tcp-bbr irqbalance

Install

Copy and paste this into your SSH client:

rm /root/cake.sh; rm /etc/init.d/cake; rm /etc/hotplug.d/iface/99-cake; rm /etc/nftables.d/*-rules.nft; wget -O /root/cake.sh "https://raw.githubusercontent.com/Last-times/CAKE-QoS-Script-OpenWrt/main/cake.sh"; chmod 755 /root/cake.sh

The cake.sh script is located in the /root/ folder on the router and you have to edit this:

1. Change the CAKE settings according to your connection type and also change the other settings (like rules, ports, IP address, irqbalance, etc.).
2. You can delete the ports and IP address from the script, because are just examples.
3. Once you've finished editing the script, use this command to run the script:

./cake.sh

Or download the script to edit it with the notepad and then place the edited script into the /root/ folder on the router, then change the permissions of the script with this command chmod 755 /root/cake.sh and run the script with the command above ./cake.sh

• GitHub: Download the script

CLI

Command to run the script:

./cake.sh

Others important commands:

# To check if the DSCP marking is working
tc -s qdisc


# To check your CAKE settings
tc qdisc | grep cake


# To check the veth devices
ip link show


# To check the nftables rules
nft list ruleset


# To check if changed the default OpenWrt settings
sysctl net.core.default_qdisc
sysctl net.ipv4.tcp_congestion_control
sysctl net.ipv4.tcp_ecn


# To check if irqbalance or packet steering are enabled or disabled
uci show irqbalance.irqbalance.enabled
uci show network.globals.packet_steering

Tip

• Don't use Software flow offloading, it will break the rules and CAKE.

Uninstall/Remove

Copy and paste this into your SSH client:

/etc/init.d/cake stop; rm /root/cake.sh; rm /etc/init.d/cake; rm /etc/hotplug.d/iface/99-cake; rm /etc/nftables.d/*-rules.nft; sed -i "/default_qdisc/d; /tcp_congestion_control/d; /tcp_ecn/d" /etc/sysctl.conf; uci set dhcp.odhcpd.loglevel="4"; uci set irqbalance.irqbalance.enabled="0"; uci del network.globals.packet_steering; uci commit && reload_config

DSCP Information

• Differentiated Services Field Codepoints (DSCP)
• RFC 8325 - Mapping Diffserv to IEEE 802.11
• RFC 8325 - WiFi QoS Mappings
• RFC 7561 - Mapping Quality of Service (QoS) Procedures of Proxy Mobile IPv6 (PMIPv6) and WLAN