Linux - NetworkingThis forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.
Welcome to LinuxQuestions.org, a friendly and active Linux Community.
You are currently viewing LQ as a guest. By joining our community you will have the ability to post topics, receive our newsletter, use the advanced search, subscribe to threads and access many other special features. Registration is quick, simple and absolutely free. Join our community today!
Note that registered members see fewer ads, and ContentLink is completely disabled once you log in.
If you have any problems with the registration process or your account login, please contact us. If you need to reset your password, click here.
Having a problem logging in? Please visit this page to clear all LQ-related cookies.
Introduction to Linux - A Hands on Guide
This guide was created as an overview of the Linux Operating System, geared toward new users as an exploration tour and getting started guide, with exercises at the end of each chapter.
For more advanced trainees it can be a desktop reference, and a collection of the base knowledge needed to proceed with system and network administration. This book contains many real life examples derived from the author's experience as a Linux system and network administrator, trainer and consultant. They hope these examples will help you to get a better understanding of the Linux system and that you feel encouraged to try out things on your own.
Click Here to receive this Complete Guide absolutely free.
I have a reverse ssh connection established from a remote machine to my local machine - it is established with autossh from the remote machine - I know it is connecting because I can see the two ssh processes on the local machine - and, when I kill the two ssh processes, two new ssh processes are immediately established.
But I cannot login to the port on the local machine. I have tried everything - it simply refuses to connect. This remote machine is miles away and not readily accessible.
ssh -p 7766 -vvv user[at_sign]192.168.1.108
OpenSSH_5.1p1 Debian-6ubuntu2, OpenSSL 0.9.8g 19 Oct 2007
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug2: ssh_connect: needpriv 0
debug1: Connecting to 192.168.1.108 [192.168.1.108] port 7766.
debug1: Connection established.
debug1: identity file /home/guest/.ssh/identity type -1
debug1: identity file /home/guest/.ssh/id_rsa type -1
debug1: identity file /home/guest/.ssh/id_dsa type -1
ssh_exchange_identification: Connection closed by remote host
I'm wondering if there is some way I could utilize netcat or socat to "tap into" this connection from my local machine??? (My ultimate goal would be to get to a shell on the remote machine.)
You would need to set that up on the remote machine BEFORE establishing
the SSH connection. SSH simply doesn't give the server a shell on the
client. So regardless if you could somehow "tap into" the connection,
you'd only end up with a shell on the sever, the local machine.
In other words:
> have a reverse ssh connection established
What you have is a normal SSH which you wish you could use in
reverse, but you can't.
To set that up BEFORE making the connection, you'd redirect the STDIN
and STDOUT to named pipes, local sockets, fifos, or some other type of IPC.
The idea is that you'd be doing something roughly similar too:
ssh otherbox.com "tail -f </tmp/input" >/bin/bash
That is, on the machine you are connectiong to, you'd be telling SSH
to read some file/socket/pipe/fifo, then redirect it's output to a local shell.
Most likely, though, to tolve your problem you need to forget everything
I just said and everything in your original post. Instead, go back a step
or two and think about what your problem is or what you need to do, as
opposed to the METHOD you've been thinking you want to use. You need to
admister a remote server/ How about connecting TO it via SSH rather than
FROM it? A KVM? IPMI? A serial ca ble connected to another remote machine?
Thanks very much for your suggestions - I think you've convinced me that even though this connection exists, there is no way to use it as it is now set up.
And yes, it is a situation where the server is behind a wireless network - and I have no control over that network. It would take a 1,200 mile plane ride to fix it. It working working at one point, but I must have done something to cause it to stop accepting ssh connections. It doesn't even give me the opportunity to login - it simply responds as you see in my first post.
Again, you have convinced me that there is no way to fix this without accessing the remote machine. It's just strange that a person is always concerned that someone will hack into his or her machine - in this case I know all the pertinent details about this remote machine - even have an established connection, but yet I am helpless!
As I mentioned in my first post, the remote machine has established a reverse ssh connection to my local machine.
So I would login to either localhost or the actual ip address of my local machine to access that reverse connection. I have found through research and experimentation that when establishing the reverse connection (from the remote machine) one is better off to specifically designate the ip address of the local machine, rather than using localhost.