iperf3¶
iperf3 - The Network Speed Measurement Tool¶
The iperf3 tool is used to measure network speeds via TCP (default) and UDP.
You need 2 nodes in order to test using iperf3.
One node acts as the server (receiver), and the other acts as the client (sender).
Using iperf3¶
You need both a server node and a client node.
Server Node¶
To start iperf3 on a node in server mode:
iperf3 -s
# or
iperf3 --server
Then you will use that machine's IP when sending from the client node.
hostname -I | awk '{ print $1 }' # if you don't know the IP
Client Node¶
On the client node, you specify the server node with -c <ip>.
iperf3 -c 192.168.200.101 -n 1G
- This tests the speed of the network using TCP packets with
1Gof data.
iperf3 -c 192.168.200.101 -n 1G -P 128
- This does the same thing, except it uses 128 parallel streams.
- This is the maximum number of parallel streams you can use in
iperf3.
- This is the maximum number of parallel streams you can use in
TCP and UDP¶
By default iperf3 will use TCP packets. When -u is used, it will use UDP packets.
The bitrate is limited for UDP. The default is 1 Mbit/sec for UDP. It's unlimited for TCP/SCTP.
Increasing the bitrate with -b better reflects network speeds with UDP.