Linux - NetworkingThis forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.
Notices
Welcome to LinuxQuestions.org, a friendly and active Linux Community.
You are currently viewing LQ as a guest. By joining our community you will have the ability to post topics, receive our newsletter, use the advanced search, subscribe to threads and access many other special features. Registration is quick, simple and absolutely free. Join our community today!
Note that registered members see fewer ads, and ContentLink is completely disabled once you log in.
If you have any problems with the registration process or your account login, please contact us. If you need to reset your password, click here.
Having a problem logging in? Please visit this page to clear all LQ-related cookies.
Get a virtual cloud desktop with the Linux distro that you want in less than five minutes with Shells! With over 10 pre-installed distros to choose from, the worry-free installation life is here! Whether you are a digital nomad or just looking for flexibility, Shells can put your Linux machine on the device that you want to use.
Exclusive for LQ members, get up to 45% off per month. Click here for more info.
I have a couple of user accounts on a RedHat 7 system (I don't have root access to this box). I am logging in from a windows box using telnet.
Whenever I change the password on one of these accounts, I can't log in via telnet again. I know telnet is OK, and the new password is OK, because I can telnet onto account A (on which the sysadmin set the password) then, in the telnet window, su to account B (on which I changed the password). I just can't telnet directly to account B. It says "login incorrect" (And the old password has stopped working too). When a sysadmin resets the password, account B is OK for telnet again.
I have been using linux for years and never seen this before. And the sysadmins don't know either.
The server uses local, shadowed passwords (no network login), telnet is started by xinetd, everthing is pretty much out-of-the-box. The passwords here are all alphabetic characters, nothing that can be scrambled by keyboard translations.
So:
What can make a user/password combination OK locally (for su, when I'm already logged in), but not via telnet?
What can break it when I change my own password, but not when root changes it?
Are you using the same pam modules for telnet and su?
To the same password?
Have you looked through the telnet and pam logs?
Not the same password, but both alphabetic.
I can't see these logs, but I can see the pam configuration files. There is not one for telnet, I guess the 'login' file is the relevent one, and they are different. I will suggest to the sysadmins that this may be the problem.
On another forum, I have been told it may be a control character on the end of my (changed) password, but I don't see how I would be able to su with that password if that was the case.
Some systems have pam modules that disallow weak passwords.
Ask root to set the passwd, then make a copy of the hash from /etc/shadow.
Then, change the passwd to the same thing yourself, and look at the hash again.
Last edited by stefan_nicolau; 03-08-2006 at 01:42 PM.
LinuxQuestions.org is looking for people interested in writing
Editorials, Articles, Reviews, and more. If you'd like to contribute
content, let us know.