SSH tunneling notes

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SSH tunneling notes

Postby lik » Wed Jun 29, 2011 10:42 am

Taken from :

-L [bind_address:]localhostport:remotehost:remoteport

Specifies that the given localhostport on the local (client) host is
to be forwarded to the given remotehost and remoteport on the remote side.
This works by allocating a socket to listen to localhostport on the local
side, optionally bound to the specified bind_address. Whenever a con-
nection is made to the local port, the connection is forwarded over
the secure channel, and a connection is made to remotehost on remoteport
from the remote machine. Note: remotehost may be any host that the
ssh endpoint machine (ie the machine specified with ''user@hostname'') can
access, not just the endpoint machine itself.

Examples forwarding a remote SMTP port to local port, where the remote
service is running on the same machine as the ssh login:

$ ssh -Nf -L \
$ telnet localhost 12345
Connected to localhost.localdomain.
Escape character is '^]'.
220 ESMTP - Mail server ready.

Example forwarding a remote web server inside a network to a local port,
where the ssh login is on a machine that can see the remote server but
not on it. This will work for any TCP service visible to the ssh login:

$ ssh -Nf -L \
$ firefox localhost:9876
(web page for protected intranet displayed.)

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Joined: Wed Dec 15, 2010 3:21 am

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