iperf

iperf is a tool for active measurements of the maximum achievable bandwidth on IP networks. It supports tuning of various parameters related to timing, protocols, and buffers. For each test it reports the bandwidth, loss, and other parameters.

• Project Homepage [EN]
  • Repository

• iperf2 [EN] @ Fedora Package
• iperf3 [EN] @ Fedora Package
• iperf2 [EN] @ Homebrew Formula
• iperf3 [EN] @ Homebrew Formula

• iperf [EN] @ Wikipedia

Documentation

• man 1 'iperf3' [EN]

Further Information

• Public iPerf3 servers [EN]

Syntax

iperf3 --server [PARAMETER ...]
iperf3 --client SERVER [PARAMETER ...]

Parameters

General parameters

The following parameters descriptions apply to the server and the client:

-f [kmgtKMGT], --format [kmgtKMGT]

Format to report: Kbits/Mbits/Gbits/Tbits.

-i NUMBER, --interval NUMBER

Pause NUMBER seconds between periodic throughput reports; default is 1, use 0 to disable.

--logfile FILE

Send output to a log FILE.

-p NUMBER, --port NUMBER

Set server port to listen on/connect to to NUMBER (default 5201).

Server

The following parameters descriptions apply only to the server:

-s, --server

Run in server mode.

-D, --daemon

Run the server in background as a daemon.

Client

The following parameters descriptions apply only to the client:

-c, --client host

Run in client mode, connecting to the specified server. By default, a test consists of sending data from the client to the server, unless the -R flag is specified.

-4, --version4

Only use IPv4.

-6, --version6

Only use IPv6.

-b NUMBER[KM], --bitrate NUMBER[KM]

Set target bitrate to NUMBER bits/sec (default 1 Mbit/sec for UDP, unlimited for TCP/SCTP). Setting the target bitrate to 0 will disable bitrate limits (particularly useful for UDP tests).

-R, --reverse

Reverse the direction of a test, so that the server sends data to the client.

-u, --udp

Use UDP rather than TCP.

Examples

Start the server...

iperf3 --server --format 'M'

... test sending data over TCP to the server

iperf3 --client 'xeon.raysoft.loc' --version4 --format 'M'

... test sending data over UDP to the server

iperf3 --client 'xeon.raysoft.loc' --version4  --format 'M' \
  --udp --bitrate 0

... and test receiving data over TCP from the server

iperf3 --client 'xeon.raysoft.loc' --version4  --format 'M' --reverse

... and test receiving data over UDP from the server

iperf3 --client 'xeon.raysoft.loc' --version4  --format 'M' --reverse \
  --udp --bitrate 0