可以使用速度测试工具： speedtest-cl
如果没有安装的话，安装一下。
apt install speedtest-cli
测试命令
直接运行：speedtest-cli --secure
服务器的输出为：
root@ns521461:~# speedtest-cli --secure
Retrieving speedtest.net configuration...
Testing from OVH SAS (158.69.124.134)...
Retrieving speedtest.net server list...
Selecting best server based on ping...
Hosted by Fibrenoire Internet (Montréal, QC) [1.79 km]: 4.256 ms
Testing download speed................................................................................
Download: 673.37 Mbit/s
Testing upload speed......................................................................................................
Upload: 186.85 Mbit/s
root@ns521461:~#
能大概测下服务器对外部网络的速度。
