Web Hosting Talk : Web Hosting Main Forums : Hosting Security and Technology : Installed PAM, config'd ssh now I cannot login

[Rclark]

I have a client with a rh 9 machine and he wanted PAM auth.. I'm not too familiar with it so I just did what he wanted.. installed the latest source and configured openssh with it. Now I cannot login to the machine at all... how do I get rid of it ?!

[sprintserve]

Did you enable telnet temporarily before recompiling openssh? If not you are pretty much screwed. Contact the datacenter to fix it for you.

[unixtx]

A RedHat 9 kickstart, typically, installs PAM authentication by default, so it should have been on the box already, unless it was specifically unselected at install time. As with all RPM-based distributions, only use bleeding edge source compiles as a last resort, and only for absolute necessity of functionality that is not in the vendor-released build, or cannot be customized with a srpm build.

Custom source compiles reek havoc on an RPM-based distro, when it comes time to perform security updates with RPM packages, unless you have carefully followed all the packages in the dependency trees. Hmm, let me guess, the original PAM RPMs were never removed, either...

[sprintserve]

Yes. Source compiles on Redhat can create all sorts of problems. (unfortunately learning from experience when I first started using Redhat distro)

PAM auth I believe has been in Redhat even since 7.x series or even earlier.

[genlee]

If you screwed up pam, you probably need to have the server booted into single user mode and have the an admin reinstall the pam rpms.

[Goni]

When you install OpenSSH from scratch, you have to compile is with '--with-pam' option. After install you *must* copy the pam file for sshd from the contrib directly to /etc/pam.d/. In this case, it will be copy openssh-3.6.1p2/contrib/redhat/sshd.pam to /etc/pam.d/sshd

If all goes well, start the sshd and you will be able to login.

btw: You might have to check with your NOC for this as you don't seem to have any shell access to the box.


Naseer