What does ssh -t do?
-t option allocates a pseudo-terminal for
ssh. This comes in handy when you want to "double
Let's say you can reach the host bastion and bastion can reach internal but you can't reach internal. No problem, right? You can log into internal like this:
ssh bastion ssh internal
No joy: "Pseudo-terminal will not be allocated because stdin is not a terminal."
Now try that again with -t...
ssh -t bastion ssh internal
And it works.