[arch-general] SSH Tunnel doubts

[David J. Haines]

On Mon, Jul 18, 2011 at 8:57 PM, Daniel Hilst Selli
<danielhilst at gmail.com>wrote:

> Em 18-07-2011 18:14, Sven-Hendrik Haase escreveu:
>
>  On 07/18/2011 10:03 PM, David J. Haines wrote:
>>
>>> And yet, it doesn't touch on forwarding of anything other than X11 data.
>>>
>>> To answer the original question, you're missing the host you're trying to
>>> connect to, but I'll fill in the blanks
>>>
>>> ssh -L X:host1:Y host2 means open a connection to host2, including shell,
>>> and forward anything sent to localhost on port X to host1 on port Y.
>>> Host1
>>> and host2 can be the same machine. This comes in useful for things like
>>> forwarding VNC securely, e.g. ssh -L 60000:remotevncserver:5901
>>> remotevncserver and then connecting to the vncserver at localhost:60000
>>>
>>> ssh -R X:host1:Y host2 means open a connection to host2, including shell,
>>> and then host2 should listen on port X for connections, which it will
>>> then
>>> send back to your local host, which will forward the connection on to
>>> host1
>>> on port Y.
>>>
>>> In your example you're missing the host you're connecting to, but I can
>>> tell
>>> you that:
>>>
>>> ssh 192.168.1.200
>>> ssh -L 1000:192.168.1.100:2000 192.168.1.100
>>>
>>> when you start from 192.168.1.100 is functionally equivalent to
>>>
>>> ssh -R 1000:192.168.1.100:2000 192.168.1.200
>>>
>>> when you start from 192.168.1.100, in that both solutions will forward a
>>> connection from 192.168.1.200:1000 to 192.168.1.100:2000 (I didn't use
>>> the
>>> port 22 from your example, as that would imply that ssh wasn't running
>>> there, so you'd need to use -p and other messiness).
>>>
>>> Hope this helps,
>>>
>>> David J. Haines
>>> dhaines at gmail.com
>>>
>>>
>>> On Mon, Jul 18, 2011 at 3:12 PM, Jeffrey Lynn Parke Jr.<
>>> jeffrey.parke at gmail.com>  wrote:
>>>
>>>  On Mon, Jul 18, 2011 at 2:05 PM, Daniel.<danielhilst at gmail.com>  wrote:
>>>>
>>>>  I have some doubts about traffic forwarding
>>>>>
>>>>> Supposing that my IP is 192.168.1.100
>>>>> and the remote is 192.168.1.200
>>>>>
>>>>> is this ->  ssh -R 1000:192.168.1.200:22
>>>>> the same as this:
>>>>> ssh 192.168.1.200
>>>>> ssh -L 1000:192.168.1.100:22
>>>>>
>>>>>
>>>>> ???
>>>>>
>>>>> --
>>>>> *"Do or do not. There is no try"*
>>>>> *  **Yoda Master*
>>>>>
>>>>>
>>>> You may want to read the wiki article for ssh.
>>>> https://wiki.archlinux.org/**index.php/SSH<https://wiki.archlinux.org/index.php/SSH>
>>>>
>>>> It is very detailed.
>>>>
>>>>
>>>> --
>>>> "Breath Deeply and Dream"
>>>>
>>>>  Please put that in the SSH article! Also, please bottom post from now
>> on.
>>
>> -- Sven-Hendrik
>>
> Thanks for all helping .. I got it.. I was using putty and that mess up the
> syntax up my head..
>
> Thanks David, your explanation was really clarifying
>
> --
> "Do or do not... there is no try" Yoda Master
>

My pleasure, and there's now a section on generic forwarding on the wiki,
right beneath the X11 forwarding section. I also included a bit about acting
as a forwarding gateway.

David J. Haines
dhaines at gmail.com