1. SSHFS
For sshfs (ssh mount), if you do not specify any mount option, when the network connection is lost (e.g., due to VPN disconnection, server down, etc.), if you access the filesystem, you will have a hard hang, not interruptible by Ctrl+C or Ctrl+Z. The solution is to add sshfs option:
"-o reconnect,ServerAliveInterval=2,ConnectTimeout=3,ConnectionAttempts=1"
2. Reliable Reverse SSH
For reverse SSH, very often the port forwarding silently fails after some time without the SSH command quitting.
The solution is to add ssh option:
"-o ServerAliveInterval=2 -o ConnectTimeout=3 -o ConnectionAttempts=1 -o ExitOnForwardFailure=yes"
3. Secure Reverse SSH
Very often, it is more secure to use reverse SSH to bind port on VPN virtual interface rather than all interfaces (i.e., 0.0.0.0, when "GatewayPorts yes" is set).
The solution is to set "GatewayPorts clientspecified" in /etc/ssh/sshd_config; and in the reverse SSH command, specify the virtual interface to bind, use "-R 10.8.0.1:1234:localhost:1234" instead of "-R 1234:localhost:1234"
