I have a raspberry pi behind a NAT and a remote virtual server.
I want to be able to access the pi via a remote shell from the outside.
To do this, I created an executable file
/etc/network/if-up.d/ssh_tunnel on the containing pi
sudo -u myname ssh-fCNR *: 2222: localhost: 22 email@example.com
Although this command works, when it is run as root from the command line, it does not work at startup.
The redirection of stderr to a file gives me
ssh: connect to the host 220.127.116.11 port 22: the network is inaccessible
What could I do better?