Recently, servers outside the domain often crash, and I'm very upset!
Steal a picture
### In the figure, only part of the device ip is marked. The scenario described below is 50.237 can only access 171.7, but due to security policies and other reasons, 171.8 cannot be directly accessed, but 171.7 can access the 171.8 server, so use xshell as a tunnel for 237 and 171.8 Inter-communication.
###Communication direction description 192.168.50.237-->192.168.171.7 (springboard)-->192.168.171.8
After opening the 192.168.171.7 terminal on 1.xshell, go to File->Properties->Connection->SSH->Tunnel, and add rules as follows:
2. Open a "local shell" in the xshell terminal and use ssh to log in (note that you need to open the 171.7 terminal first). The following figure shows that the login terminal after executing the command ssh 127.0.0.1 2222 from the "local shell" is 192.168.171.8. The expected effect is the same as when Xftp is opened.