First, visit http://www.ngrok.cc/login.html , registration, login, open tunnel.
Second, open the virtual machine Kali, the next good move clients into Kali, decompress, run
1, extract
unzip linux_and64.zip
2, download shellinabox
apt install shellinabox
3, run shellinabox, and check the port.
shellinabox -b -t netstat -ntulp |grep 4200
4, create a resource account to view map
useradd 123 passwd 123
5, run sunny
./sunny clientid 8ace6b91eca3f2f2 (your tunnel id)
6, domain names acquired, enter the account password to access your Linux system.