Iperf 是一个网络性能测试工具。Iperf可以测试最大TCP和UDP带宽性能，具有多种参数和UDP特性，可以根据需要调整，可以报告带宽、延迟抖动和数据包丢失。
使用环境：VPS是centos7_64位系统标准安装，如果提示没有wget、rpm、yum命令请自行安装，系统update的iperf是3.1.3版本，默认安装2.0

安装iperf：
[root@fq ~]# wget https://iperf.fr/download/fedora/iperf3-3.1.3-1.fc24.x86_64.rpm
--2020-03-01 11:10:00--  https://iperf.fr/download/fedora/iperf3-3.1.3-1.fc24.x86_64.rpm
Resolving iperf.fr (iperf.fr)... 213.246.63.45, 2a00:c70:1:213:246:63:45:2
Connecting to iperf.fr (iperf.fr)|213.246.63.45|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 78686 (77K) [application/x-redhat-package-manager]
Saving to: ‘iperf3-3.1.3-1.fc24.x86_64.rpm’

100%[=======================================>] 78,686       144KB/s   in 0.5s

2020-03-01 11:10:01 (144 KB/s) - ‘iperf3-3.1.3-1.fc24.x86_64.rpm’ saved [78686/78686]

[root@fq ~]# rpm -Uvh iperf3-3.1.3-1.fc24.x86_64.rpm
Preparing...                          ################################# [100%]
Updating / installing...
1:iperf3-3.1.3-1.fc24              ################################# [100%]
[root@fq ~]# yum update
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile

• base: centos.cs.nctu.edu.tw
• elrepo: mirror-hk.koddos.net
• elrepo-kernel: mirror-hk.koddos.net
• epel: fedora.cs.nctu.edu.tw
• epel-debuginfo: fedora.cs.nctu.edu.tw
• extras: mirror.upsi.edu.my
• updates: mirror.its.sfu.ca
  Resolving Dependencies
  --> Running transaction check
  ---> Package iperf3.x86_64 0:3.1.3-1.fc24 will be updated
  ---> Package iperf3.x86_64 0:3.1.7-2.el7 will be an update
  --> Finished Dependency Resolution

Dependencies Resolved

=================================================================================
Package          Arch             Version                  Repository      Size
=================================================================================
Updating:
iperf3           x86_64           3.1.7-2.el7              base            79 k

Transaction Summary
=================================================================================
Upgrade  1 Package

Total download size: 79 k
Is this ok [y/d/N]: y
Downloading packages:
Delta RPMs disabled because /usr/bin/applydeltarpm not installed.
iperf3-3.1.7-2.el7.x86_64.rpm                             |  79 kB  00:00:00    
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Warning: RPMDB altered outside of yum.
Updating   : iperf3-3.1.7-2.el7.x86_64                                     1/2
Cleanup    : iperf3-3.1.3-1.fc24.x86_64                                    2/2
Verifying  : iperf3-3.1.7-2.el7.x86_64                                     1/2
Verifying  : iperf3-3.1.3-1.fc24.x86_64                                    2/2

Updated:
iperf3.x86_64 0:3.1.7-2.el7

Complete!
[root@fq ~]# yum install iperf
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile

• base: centos.cs.nctu.edu.tw
• elrepo: mirror-hk.koddos.net
• elrepo-kernel: mirror-hk.koddos.net
• epel: mirrors.aliyun.com
• epel-debuginfo: mirrors.aliyun.com
• extras: mirror.upsi.edu.my
• updates: mirror.kku.ac.th
  Resolving Dependencies
  --> Running transaction check
  ---> Package iperf.x86_64 0:2.0.13-1.el7 will be installed
  --> Finished Dependency Resolution

Dependencies Resolved

=================================================================================
Package         Arch             Version                   Repository      Size
=================================================================================
Installing:
iperf           x86_64           2.0.13-1.el7              epel            86 k

Transaction Summary
=================================================================================
Install  1 Package

Total download size: 86 k
Installed size: 185 k
Is this ok [y/d/N]: y
Downloading packages:
iperf-2.0.13-1.el7.x86_64.rpm                             |  86 kB  00:00:01    
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Installing : iperf-2.0.13-1.el7.x86_64                                     1/1
Verifying  : iperf-2.0.13-1.el7.x86_64                                     1/1

Installed:
iperf.x86_64 0:2.0.13-1.el7

Complete!
[root@fq ~]# iperf -v
iperf version 2.0.13 (21 Jan 2019) pthreads
[root@fq ~]# iperf -s -u

Server listening on UDP port 5001
Receiving 1470 byte datagrams
UDP buffer size:  208 KByte (default)

[  3] local 10.140.0.3 port 5001 connected with 182.120.21.91 port 64702
[ ID] Interval       Transfer     Bandwidth        Jitter   Lost/Total Datagrams
[  3]  0.0-60.3 sec  75.3 MBytes  10.5 Mbits/sec  15.785 ms 456497/510203 (89%)