Go to iperf Parameters

Iperf is a performance measurement tool for TCP/IP and UDP/IP. It provides network throughput information, as well as statistics such as vibration, packet loss rate, maximum segment, and maximum transmission unit size; this helps us test network performance and locate network bottlenecks.
Parameter description
-S starts in server mode. For example: iperf-s
-C is started in client mode. The host is the server address, for example, iperf-c 222.35.11.23.
Common Parameters
-F [k | m | K | M]: displays reports in Kbits, Mbits, KBytes, and MBytes. The default value is Mbits. For example: iperf-c 222.35.11.23-f K.
-I sec displays the report interval in seconds. For example: iperf-c 222.35.11.23-I 2
Iperf is the client that sends data to the server.
The server displays the receiving rate. It is best to add the I parameter for Rate Tracking.
The client displays the sending rate.
Server display receiving rate
-L buffer size, 8 KB by default, eg: iperf-c 222.35.11.23-l 16
You can use different packages for testing.
-M: displays the maximum mtu value of tcp.
-O Outputs Reports and error messages to the file eg: iperf-c 222.35.11.23-o c: \ iperflog.txt
-P specifies the port used by the server or the port connected by the client, such as: iperf-s-p 9999; iperf-c 222.35.11.23-p 9999
-U uses udp protocol
It is best to use udp when testing htb. The udp communication overhead is small, and the test bandwidth is more accurate.
-W: Specifies the TCP window size. The default value is 8 KB.
If the window is too small, packet loss may occur.
-B binds a host address or interface (this parameter is used when the host has multiple addresses or interfaces)
-C is compatible with the old version (used when the server and client versions are different)
-M: sets the maximum mtu value of TCP packets.
-N: set no TCP latency
-V transmission of ipv6 data packets
Server-specific parameters
-D run ipserf, eg: iperf-s-D as a service
-R stops the iperf service. For-D, eg: iperf-s-R
Dedicated client Parameters
-D. Perform bidirectional transmission test at the same time.
-N indicates the number of bytes transmitted. For example, iperf-c 222.35.11.23-n 100000
-R independent bidirectional transmission test
-B indicates the sending bandwidth. The default value is 1 Mbit/s.
This is the most useful parameter when testing qos.
-T test time. The default value is 10 seconds. For example, iperf-c 222.35.11.23-t 5.
The default value is 10 s.
-F specifies the file to be transferred
-T specifies the ttl value.