2. Check whether the firewall settings of the local host prevent SSH connection. Yes, you need to open an SSH port in the firewall or add a white list of SSH services.
3. Check whether the network connection between the local host and the target host is normal. You can check the connectivity between the local host and the target host through the ping command or other network testing tools.
4. Confirm whether the SSH tunnel command is correct. SSH tunnel command needs to specify parameters such as local host, target host and port. If the parameters of the SSH tunnel command are incorrect, SSH tunnel forwarding will fail. You can refer to the SSH tunnel command manual for operation.
5. If you use public key authentication, you need to confirm whether the public key is correct. If the public key is incorrect, the SSH connection cannot be established, resulting in the failure of SSH tunnel forwarding.
6. You can try to add the -v parameter to the command line, so as to view the detailed debugging information and help find out the reasons for the failure of SSH tunnel forwarding.