EasyTC

Simple program for easy, basic tc rule creation and management. Supported features are:

• filter by IP and port
• apply max rate (link speed), latency, packet loss
• show all qdisc, filters and compiled rules
• reset/remove rules

Note on kernel

The kernel module sch_netem is required. Easytc will automatically attempt to modprobe it if need be.

On some distros, extra packages must be installed to add netem module. For example on RH-based distros: yum install kernel-modules-extra iproute-tc.

CLI Usage

Help

$ ./easytc --help
Usage:
  easytc [OPTIONS] <command>

Help Options:
  -h, --help  Show this help message

Available commands:
  del    delete a tc rule
  reset  remove all tc rules
  set    create a tc rule
  show   list tc rules or interfaces

$ ./easytc set --help
Usage:
  easytc [OPTIONS] set [set-OPTIONS]

Help Options:
  -h, --help            Show this help message

[set command options]
      -i, --interface=  specify an interface for the rule
      -s, --src-ip=     optional: filter by source IP
      -d, --dst-ip=     optional: filter by destination IP
      -S, --src-port=   optional: filter by source port
      -D, --dst-port=   optional: filter by destination port
      -l, --latency-ms= optional: specify latency (number) of milliseconds
      -p, --loss-pct=   optional: specify packet loss percentage
      -e, --rate-bytes= optional: specify link speed rate, in bytes

Show Interfaces

$ ./easytc show iface
enp0s5

Apply a rule

Note that if the interface switch is not provided a rule for every interface will be created.

$ ./easytc set -s 10.0.0.0/8 -d 8.8.8.8 -l 100 -p 20

Test

$ ping 1.1.1.1
PING 1.1.1.1 (1.1.1.1) 56(84) bytes of data.
64 bytes from 1.1.1.1: icmp_seq=1 ttl=128 time=22.9 ms
64 bytes from 1.1.1.1: icmp_seq=2 ttl=128 time=27.8 ms

$ ping 8.8.8.8
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_seq=1 ttl=128 time=124 ms
64 bytes from 8.8.8.8: icmp_seq=3 ttl=128 time=127 ms

Show Rules

$ ./easytc show rules
 Iface   SrcIP       DstIP    SrcPort  DstPort  LatencyMs  PacketLossPct  RateBytes  TcFlowID  TcQdiscHandle  TcFilterHandle 
-----------------------------------------------------------------------------------------------------------------------------
 enp0s5  10.0.0.0/8  8.8.8.8                    100        20.00                     1:3       30:            800::800   

Show all rules and interfaces, in json format

$ ./easytc show all
[...]

Remove all rules

$ ./easytc reset

As golang package

All exported functions are defined in easytc/tc package, used in easytc/cli. See the simple CLI implementation for exact usage.