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Agent Forwarding Question for the list

Subject: Agent Forwarding Question for the list
Date: Wed, 04 Oct 2006 18:18:02 -0400
I have looked through the archives and googled this pretty thoroughly, I'm having a tough time finding someone else who has asked the same question previously. There's a lot of information about openssh, but surprisingly little detail about port forwarding. Either it works for everyone all the time, or my configuration is a little bit particular compared to others.

We would like to change from ssh2 to openssh for all of our linux servers. I am testing new equipment with Fedora Core 5 with openssh configured out of the box. I have no need to forward X11 windows, I just want to be able to jump from machine to machine with a terminal, ssh and scp, and use different accounts without having to type a password. A lot of our production process revolves around this, so it pretty much has to work for me to convert us.

I made users and keys with openssh instead of using the old ones, put them in the accounts I wanted to jump to on multiple servers. I set the perms on the authorized_keys files to 600. I set the ssh_config file in /etc/ to say ForwardAgent yes.

Now let's say that I have a linux desktop and two linux servers, assuming I've configured things correctly, then from the desktop box I should be able to:

me@desktop> ssh-add
            (type pass for key)
me@desktop> ssh someuser@server1

now from that terminal
someuser@server1> ssh otheruser@server2

It asks me for a password when I try to jump to the second server. I can put the password in and it works, but I think at this point it should be forwarding the key.

I have tail -f running on the secure log on each machine in question so I can see if there's anything happening.

It does not enter into the log on the target machine that I am attempting to open a connection while it waits for a password, so I was thinking that pam may be intercepting the request and demanding one.

Has anyone known pam to do such a thing?
Am I seeing a common non-error?
Is this a situation where ssh-agent on the servers may be interfering with the one from the desktop?
Do I have to turn on X11forwarding to get agent forwarding on these servers, which don't even have x installed?
Does this have something to do with xauth on the servers, or is that only for x11 forwarding?


Thanks

Jason Powers

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