1）端口扫描
nc -v -w 2 192.168.2.34 -z 21-24
nc: connect to 192.168.2.34 port 21 (tcp) failed: Connection refused
Connection to 192.168.2.34 22 port [tcp/ssh] succeeded!
nc: connect to 192.168.2.34 port 23 (tcp) failed: Connection refused
nc: connect to 192.168.2.34 port 24 (tcp) failed: Connection refused
2)从192.168.2.33拷贝文件到192.168.2.34
在192.168.2.34上： nc -l 1234 > test.txt
在192.168.2.33上： nc 192.168.2.34 < test.txt
3)简单聊天工具
在192.168.2.34上： nc -l 1234
在192.168.2.33上： nc 192.168.2.34 1234
4) 拷贝文件带进度
cat CentOS-6.9-x86_64-bin-DVD2.iso |pv -b | nc 45.55.0.86 9999
5) rsync拷贝文件带进度
rsync -v -W --progress worker@in-test-cv-server-1:/home/worker/jianli.yang/research/video_cla/video_1/video_7.tar ./
