LinuxQuestions.org
Download your favorite Linux distribution at LQ ISO.
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Networking
User Name
Password
Linux - Networking This forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.

Notices


Reply
  Search this Thread
Old 03-07-2006, 08:24 AM   #1
dgwsoft
LQ Newbie
 
Registered: Mar 2006
Posts: 6

Rep: Reputation: 0
Telnet won't recognise new passwords on RH7


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?

any ideas anyone ?
 
Old 03-07-2006, 05:49 PM   #2
arno
Member
 
Registered: Jul 2004
Location: Netherlands
Distribution: fedora core 8, suse 10.3, ubuntu 7.10, kamikaze 7.09
Posts: 515

Rep: Reputation: 30
Have you tried the following:

1) login as usera
2) sudo passwd userb

or

2a) su -l
2b) passwd userb
 
Old 03-07-2006, 08:31 PM   #3
stefan_nicolau
Member
 
Registered: Jun 2005
Location: Canada
Distribution: Debian Etch/Sid, Ubuntu
Posts: 529

Rep: Reputation: 32
Are you using the same pam modules for telnet and su?

Quote:
What can break it when I change my own password, but not when root changes it?
To the same password?

Have you looked through the telnet and pam logs?
 
Old 03-08-2006, 11:54 AM   #4
dgwsoft
LQ Newbie
 
Registered: Mar 2006
Posts: 6

Original Poster
Rep: Reputation: 0
Quote:
Originally Posted by arno
Have you tried the following:

1) login as usera
2) sudo passwd userb

or

2a) su -l
2b) passwd userb
Unfortunately I don't have root access, or sudo access to passwd. But thanks for the suggestion.
 
Old 03-08-2006, 12:01 PM   #5
dgwsoft
LQ Newbie
 
Registered: Mar 2006
Posts: 6

Original Poster
Rep: Reputation: 0
Quote:
Originally Posted by stefan_nicolau
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.

Thanks.
 
Old 03-08-2006, 01:33 PM   #6
stefan_nicolau
Member
 
Registered: Jun 2005
Location: Canada
Distribution: Debian Etch/Sid, Ubuntu
Posts: 529

Rep: Reputation: 32
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.
 
  


Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off



Similar Threads
Thread Thread Starter Forum Replies Last Post
No telnet from LAN into RH7.1 box mcbleyerveld Linux - Networking 4 08-27-2004 09:42 AM
Telnet Passwords siddharth Linux - Networking 2 09-01-2003 01:22 AM
Telnet problems with RH7.2 puneet7 Linux - Networking 0 04-18-2002 07:05 PM
enable telnet on RH7.1 systray Linux - Newbie 1 03-22-2002 12:34 PM
Cannot telnet into RH7.1 as root Lemon Songster Linux - Networking 11 08-23-2001 02:31 PM

LinuxQuestions.org > Forums > Linux Forums > Linux - Networking

All times are GMT -5. The time now is 12:20 AM.

Main Menu
Advertisement
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration