My setup is the following:node A is where I startnode B is the gateway machinenode C is the destination.From Ato B I have setup SSH public key authentication but from B to C I am not allowed to.So from node A I use the following incantation which actually works from a different machine (Ubuntu 14.04):sshpass -p secretpass ssh -oProxyCommand=ssh -W %h:%p username@B username@C… however, when I try from a different location with another machine (Ubuntu 16.04 - though I doubt that's relevant), the invocation of sshpass promptly returns without any kind of output and an exit code (obtained with echo $?) of 6.More puzzling is the fact that if I do the steps separately, they succeed:A: $ ssh username@B   (directly access B without being prompted for password)B: $ ssh username@C   (prompted for password, provided 'secretpass')C: $                  (reached my destination)
sshpass failing with exit code 6
ssh