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Please can anyone help - when launching Putty from a desktop machine is it possible to pass the value of the IP address of the Windows machine to the server session?

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Well, do you want the IP that the windows machine thinks it is, or the IP that the server thinks the windows machine is? These may be different because of NAT. –  Aaron Dec 2 '11 at 22:24
Ideally I want the IP that the windows machine thinks it is because I'd like to use in conjuction with DISPLAY=10.X.X.X:0.0 export DISPLAY –  naffcat Dec 2 '11 at 22:32
Many thanks - the way I'm using a Xwindows is a bit unusal - basically I launch Exceed - the do the above command with the IP. Can you tell me where this $SSH_CLIENT variable comes from - it's there on my initial login, is it being set in profile anywhere? I ask as when I sudo to another account it's gone ... is there a way to keep it? –  naffcat Dec 3 '11 at 11:13

3 Answers 3

If you are trying to figure out the information of the SSH client from the server after the client is connected, then look at the SSH_CLIENT variable that is probably set.

echo $SSH_CLIENT 62221 22
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That works! Thankyou! - However I now realise I need to carry this into another sudo - is that possible? –  naffcat Dec 2 '11 at 23:01
Uhm, sure, something like this maybe? sudo bash -c "export MYTEST=${SSH_CLIENT%% *}; export" Do see the link I posted, if you are just looking for normal SSH X11 forwarding though. –  Zoredache Dec 2 '11 at 23:56

Yes. You can do things like:

putty -telnet
putty -ssh
putty -serial com4

Here are the various cli arguments you can pass to the executable:


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This doesn't answer the question. The arguments you posted are simply to connect to the server at the given IP address; the OP's question is to determine the client's IP address from the shell and apply the address to an environment variable. –  Jonathan J Dec 3 '11 at 5:03
Yeah, sorry -- completely misunderstood the question. Zoredache has the actual answer. =) –  Cypher Dec 5 '11 at 20:17

ideally I want the IP that the windows machine thinks it is because I'd like to use in conjuction with DISPLAY=10.X.X.X:0.0 export DISPLAY

Can't you just tick Enable X11 Forwarding on Connection->SSH->X11 ?

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Thanks, that created a file .Xauthority file in my home folder but I'm not sure what I can do with it? –  naffcat Dec 2 '11 at 22:58
Presumably you have an Xserver running on your windows system so at a shell prompt run an X11 program ? e.g. firefox & –  Iain Dec 2 '11 at 23:02

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