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Im want to send traffic over to Host B on port 3000, i have access to all nodes in this drawing, the only port that is open between these two lans is port 80 from Linux Box B to Linux box A.

so i do a "ssh -R 1206: disp@ -p 80", and ssh back trough the tunnel with "ssh -L 3000: disp@localhost -1206"

if im correct this now listens to port 3000 on the Linux Box A and sends it to Linux Box B trough the tunnel to port 3000? are my logic correct?

how can i now route this traffic over to port 3000 on host B.

and if i want t two way connection "From B to A" how can this be done?

ssh tunneling

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1 Answer 1

up vote 1 down vote accepted

IMO your routing is/IP ranges are kind of weird but I guess that's not part of the problem.

I'm working a bit on guesses but I hope it's still of some help.

linux_box_b$ ssh -g -R *:3000: disp@ -p 80

now if you send something from host_a to linux_box_a:3000 it actually gets sent to host_b:3000. For this to work the sshd on Linux Box A has to allow GatewayPorts and AllowTcpForwarding

for the other direction use

linux_box_b$ ssh -g -L *:3000: disp@ -p 80

now Linux Box B listens on port 3000 an tunnels them to Host A port 3000.

With this solution though always the last part of the connection (between Host A and Linux Box A and on the other side Host B and Linux Box B) is not encrypted.

for an end to end encrypted tunnel you could use:

linux_box_b$ ssh -g -R *:10022: disp@ -p 80
linux_box_b$ ssh -g -L *:10022: disp@ -p 80

host_a$ ssh -L 33000:localhost:3000 -p 10022

host_b$ ssh -L 33000:localhost:3000 -p 10022

now each host (a&b) will have to use localhost:33000 as their sending destination.

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'*' should be in quotes lest it get expanded by your shell. – BMDan Oct 4 '10 at 17:51
might be... i'm using bash on Mac OS X and never had that problem, but as always with shell expansion you can never be careful enough. – Marcel G Oct 4 '10 at 18:31
very nice, aye the IP ranges are weird and wrong i just picked random ips on the first lan, for the exsample, for easy reading, and the host A shold be in the exsample not,,, got it working ty mate :) – Darkmage Oct 5 '10 at 8:43

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