ssh -qTfnN -D LocalPort remotehost
All the added options are for a ssh session that’s used for tunneling.
-q :- be very quite, we are acting only as a tunnel.
-T :- Do not allocate a pseudo tty, we are only acting a tunnel.
-f :- move the ssh process to background, as we don’t want to interact with this ssh session directly.
-N :- Do not execute remote command.
-n :- redirect standard input to /dev/null.
In addition on a slow line you can gain performance by enabling compression with the -C option.