HOWTOs, tips and tricks

HOWTO test network bandwidth and latency

Links:

• iPerf3
• MTR

Prerequisites

In order to measure network bandwidth you need two hosts. We will say one of them is a server and second one is a client. We will collect information about connections between them.

Install iperf3 tool on both a server and a client:

apt-get install -y iperf3

Install mtr tool on a client:

apt-get install -y mtr

Prepare a server

Choose a port (default one is 5001) and keep it in PORT environment variable. Run iperf3 in a server mode on a server side for both TCP and UDP protocols:

PORT=5001
iperf3 -s -p $PORT
iperf3 -s -u -p $PORT

Ensure TCP and UDP ports are opened and ICMP traffic is allowed by the server.

Collecting latency

On a client side use mtr to measure latency. I used HOST variable to keep name of the server here and below:

HOST=192.168.0.1
mtr -r -c 60 -4 -o 'LDRS NBAWVG JMXI' $HOST

Collecting bandwidth

On a client side use iperf3 to collect bandwidth information. Use -R to measure a bandwidth in reverse direction:

PORT=5001

echo "Collecting bandwidth information TCP"
iperf3 -c $HOST -p $PORT -V -4 -t 60 --get-server-output
iperf3 -c $HOST -p $PORT -V -4 -t 60 --get-server-output -R

echo "Collecting bandwidth information UDP"
iperf3 -c $HOST -p $PORT -V -4 -t 60 --get-server-output -u -b 30m
iperf3 -c $HOST -p $PORT -V -4 -t 60 --get-server-output -u -b 30m -R