entering a double-hop machine using ssh

Question

I'm trying to access machine C from my local machine (A). I have ssh-keys with B, which happens to have ssh-keys with C, so I'm trying to:

ssh -X user_B@ip_B "ssh -X user_C@ip_C"

but this doesn't connect (gave "Connection to ... closed." after about a minute), and also gives back:

Pseudo-terminal will not be allocated because stdin is not a terminal.

The error message is solved by adding -tt but I'm still stuck with no conection.

This works if I do the ssh in two steps, i.e. first, connect to B, and then, once I'm in B's terminal, connect to C...

Tried also this solution. Didn't work.

When you say you did `-tt`, was that for C? Should probably be `ssh -t B "ssh C". What do you get with `-v` ? — jhnc, Feb 06 '19 at 08:41
You probably should have stayed on [Ask Ubuntu](http://askubuntu.com/). "Double hop" machines are usually (often?) called "jump boxes". Also see questions like [SSH into remote host using jump box](https://serverfault.com/q/909026/145545) on [Server Fault](http://serverfault.com/). Jump boxes usually refer to a machine in the DMZ. They are not limited to SSH. They show up in Windows networks with the RDP protocol, too. — jww, Feb 06 '19 at 12:43

score -1 · Answer 1 · answered Feb 06 '19 at 08:40

-1

This works for me:

ssh -t user_B@ip_B "ssh -t user_C@ip_C"

answered Feb 06 '19 at 08:40

jvdmr

well, it doesn't for me – CIsForCookies Feb 06 '19 at 08:44
1

Ok try to provide debug information. add `-vvvv` for both ssh and share them via pastebin. – Raja G Feb 06 '19 at 08:49
1

I added my ssh key to machine C and now it is working. Not sure if the key was the fix (I think not, but now the problem does not reproduce) – CIsForCookies Feb 06 '19 at 08:54
Ah, quite possible, I did in fact have my local ssh key installed on both servers I tested this with. – jvdmr Feb 06 '19 at 09:08

1 Answers1