LinuxQuestions.org
Help answer threads with 0 replies.
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Newbie
User Name
Password
Linux - Newbie This Linux forum is for members that are new to Linux.
Just starting out and have a question? If it is not in the man pages or the how-to's this is the place!

Notices


Reply
  Search this Thread
Old 11-23-2009, 10:07 PM   #1
Ckteo
LQ Newbie
 
Registered: Nov 2009
Posts: 7

Rep: Reputation: 0
Red Hat enterprise Linux v5-Keeps prompting for username & password while loggin in


Hi,

I was trying to log into root but the username prompts keeps coming back after I typed in the password. It was not an incorrect password but it's going to expire in 3 days.

When I tried to change the root password, I get a "Module is unknown" message.

Anyone knows how I can get logged in?

I have went through with the red hat support but in vain. I can only remember we checked the following:

/etc/pam.d/system-auth
/etc/passwd
/etc/shadow
/etc/security/opasswd
/root/.bash_profile
/etc/pam.d/system-auth
check Selinux status


As I am quite new to Linux, I have been going through the thread but failed to find any possible solution to this issue.

I would really appreciate if anyone here can provide some help. Thanks in advance.
 
Old 11-23-2009, 10:52 PM   #2
pixellany
LQ Veteran
 
Registered: Nov 2005
Location: Annapolis, MD
Distribution: Arch/XFCE
Posts: 17,802

Rep: Reputation: 738Reputation: 738Reputation: 738Reputation: 738Reputation: 738Reputation: 738Reputation: 738
Try re-booting into single-user mode:
Reboot
When the grub menu appears, hit any key to stop the count
Select the desired OS to boot, and hit "e" for edit.
Select the kernel line and "e" again
At the end of the kernel line, add "single" (no quotes)
Enter and then "b" to boot.

It should come up in a root terminal with no password required. You can then enter a new password using "passwd root"
 
Old 11-24-2009, 02:50 AM   #3
Ckteo
LQ Newbie
 
Registered: Nov 2009
Posts: 7

Original Poster
Rep: Reputation: 0
Hi Pixellany,

Thanks for the quick response, but I was still unable to change any password or log into linux.

I was able to boot into single user mode, but the same error about unknown module still appears when I tried to change the root password.

The problem was it immediately went back to prompt me for username and password after I have keyed the password.
The red hat support staff went through with me and verify that my password is expiring but still can use. I just dun know why it cannot get authenticated to log in.

Any further suggestion is appreciated. Thanks.
 
Old 11-24-2009, 03:03 AM   #4
Ckteo
LQ Newbie
 
Registered: Nov 2009
Posts: 7

Original Poster
Rep: Reputation: 0
Can I use a rescue disk to change the root password? I heard we can do that but I have also consulted the red hat support ppl, and the support staff doesn't recommend it but he couldn't tell me his concerns.
He say that the installation disk is supposed to be used only for irreversible changes to system.

Can anyone give me a second opinion? Any comment is appreciated. Thanks.
 
Old 11-24-2009, 08:52 AM   #5
pixellany
LQ Veteran
 
Registered: Nov 2005
Location: Annapolis, MD
Distribution: Arch/XFCE
Posts: 17,802

Rep: Reputation: 738Reputation: 738Reputation: 738Reputation: 738Reputation: 738Reputation: 738Reputation: 738
I'm puzzled about the "unknown module". Are those the exact words?

If I enter a nonsense word in a bash terminal, I get: "command not found"
 
Old 11-24-2009, 10:33 PM   #6
Ckteo
LQ Newbie
 
Registered: Nov 2009
Posts: 7

Original Poster
Rep: Reputation: 0
Hi,

The exact words is "Module is Unknown"

I have a feeling that the password file or something is corrupted or something like that.
Somehow, the authentication process was not processed or have errors, and the system just return me back to the log in screen.

Below is a representation of the screen during log in attempts under normal condition -

notes2_nt login: root
Password: XXXXXXXXX

the next moment, it shows:
notes2_nt login: _

==================================================================================================== ======================================

I had some assistance from someone and we use the command "cat /etc/passwd" and "more /etc/passwd" to check any existing users and tried to use them, but I do not have the passwords. When I use a wrong password, the system will return an error message saying "Login Incorrect"

Below are 2 representations of the screen during my attempts to change passwords.

E.g 1 - Changing the root password
sh-3.1# passwd root
Changing password for user root.
passwd: Module is unknown
sh-3.1#

[U]E.g 2 - Changing another username password; username: notes
sh-3.1# passwd notes
Changing password for user notes.
passwd: Module is unknown
sh-3.1#

Description to the above examples:
It doesn't allow me to change any password even under the shell prompt.

Do let me know if there is anything I could do or any further checks I should take to isolate the problem. Thanks a million guys.
 
Old 11-24-2009, 10:45 PM   #7
chrism01
LQ Guru
 
Registered: Aug 2004
Location: Sydney
Distribution: Centos 6.9, Centos 7.3
Posts: 17,417

Rep: Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397
1. If it says 'module is unknown' I'd expect it to mean that a pam module that is being called doesn't exists, or there is a typo in the module name being called.
Also check the ownerships/perms for all the pam modules.

2. you can reboot the server from the install media; at the initial prompt enter

linux rescue

and follow the prompts.

Prob best to clear the root passwd. Ensure you create an admin user in sudoers file with ALL privs, so you can work on the problem.
Do other userids have this issue or only root?
 
Old 11-25-2009, 10:16 PM   #8
Ckteo
LQ Newbie
 
Registered: Nov 2009
Posts: 7

Original Poster
Rep: Reputation: 0
Hi Chris,

This is a Notes server so no users will come here to log into the OS. I've tried using the single user mode to change another username account's password. Same problem occurred.. It says, 'Module is unknown' :S

Thanks for the tip. I guessed I will have to check out your suggestion later.. cos now I am having a new problem as I can't get the CDROM drive to boot from the install disk.. It seem to always bypass the CDROM drive (even though I have ensure that CDROM is the first boot device in the BIOS) and goes directly to boot from the OS itself.

Let you guys knows if I am successful after I managed to get it boot from the CDROM. Thanks guys. Really appreciate all the help here..

Regards,

Cher Kian, Teo
 
Old 11-26-2009, 07:29 PM   #9
chrism01
LQ Guru
 
Registered: Aug 2004
Location: Sydney
Distribution: Centos 6.9, Centos 7.3
Posts: 17,417

Rep: Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397Reputation: 2397
Just double check the install media by booting another system from it...
 
Old 11-21-2010, 03:42 AM   #10
pedram9
LQ Newbie
 
Registered: Nov 2010
Posts: 4

Rep: Reputation: 0
Not sure if this was solved or not, but I found this thread through Google when having a similar problem with logging in.

I was able to solve it with the steps outlined here, in case anyone else comes across this thread with a similar problem.
 
  


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
SWAT is prompting for a username/password jdklein1975 Linux - Newbie 2 07-23-2008 06:08 PM
Postfix, SASL with MySQL prompting for username and password acecomp Linux - Software 2 02-16-2005 03:04 PM
i forgot my username and password, how can i open my red hat linux? josephgiselle Linux - Software 2 06-29-2004 10:21 AM
username password forgotten red hat 9 scrollcap Linux - General 1 01-10-2004 08:24 PM

LinuxQuestions.org > Forums > Linux Forums > Linux - Newbie

All times are GMT -5. The time now is 12:39 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
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration