topic Re: Root logon denied at console. in Operating System - Linux

Root logon denied at console.

Adam W. — Tue, 02 Sep 2008 17:17:14 GMT

Ok I have a Red Hat 3.0 box, and root has been disabled to logon from the console. The IP addresses have not been set for it's new location, so I cannot remote in. There are no other accounts on the box at the moment. How can I get into this server?

Re: Root logon denied at console.

Gokul Chandola — Wed, 03 Sep 2008 03:16:05 GMT

Dear Adam,

Reboot the Linux machine by pressing the hardware reset button. In a default Linux installation, pressing CTL+ALT+DEL

Upon Linux booting up to GRUB loader GUI, move the arrow key up/down to highlight and select the Linux kernel and press e to edit the GRUB commands before booting.

Next, move the arrow key up/down to select the Linux kernel and press e again.

Append a single space followed by the word single at the end of edited line: - single

After pressing ENTER key, you should now have a similar GRUB screenshot as of follow. Keep the Linux kernel highlighted and press b to boot up with the â singleâ keyword, which will boot Linux into single user maintenance mode.

Once the Linux boot up completely into single user maintenance mode, the Linux command prompt is ready to execute command. Now, you can type passwd to reset the forgotten root password - without prompting for old root password, just type a new root password and re-type to confirm.

Done. Type reboot or exit to reboot. On next boot up, you can login with the new root password!

You Can follow the atteched file also.

Regards,
Gokul Chandola

Re: Root logon denied at console.

Adam W. — Wed, 17 Sep 2008 14:48:58 GMT

gokul,
Will doing the above, change the root console logon setting. The problem isn't that I don't know the password. I know the password. but root logon is disabled form the console.

Can I change the I.P. adress in single user mode?

Re: Root logon denied at console.

Court Campbell — Wed, 17 Sep 2008 15:46:11 GMT

go into single user mode and check that console is in the file /etc/securetty.

Re: Root logon denied at console.

Adam W. — Wed, 17 Sep 2008 16:28:48 GMT

Court,

Thanks for the info I will write mroe when I have the outcome.

Re: Root logon denied at console.

skt_skt — Wed, 17 Sep 2008 17:00:13 GMT

Can I change the I.P. adress in single user mode?

yes you can. BUT STILL U NEED TO LOGIN FIRST.

Re: Root logon denied at console.

Adam W. — Fri, 19 Sep 2008 11:21:13 GMT

Court,
I was able to get into the box using your process. Basically I went in single user mode reset the IP and subnet and was able to remote in. Weird thing is that "console" is in the /etc/securetty file, but I still cannot log into the console as root. Any other conflicting files that would not allow root to login from the console?

Re: Root logon denied at console.

Ivan Ferreira — Fri, 19 Sep 2008 12:04:34 GMT

Maybe the /etc/security/access.conf file.

Re: Root logon denied at console.

Court Campbell — Fri, 19 Sep 2008 12:29:27 GMT

Can you login as root via any other method? And can anyone else login to the console?

Re: Root logon denied at console.

Adam W. — Fri, 19 Sep 2008 12:49:58 GMT

everyone can log on remotely via tectia client. However NO ONE can logon to the console.

Re: Root logon denied at console.

Adam W. — Fri, 19 Sep 2008 12:50:59 GMT

Ivan,
What entry would I be looking for in the File you mentioned?

Re: Root logon denied at console.

Court Campbell — Fri, 19 Sep 2008 15:38:48 GMT

in access.conf you would look anything that has a combo of -, root, and either LOCAL or console.

Re: Root logon denied at console.

Court Campbell — Fri, 19 Sep 2008 15:52:24 GMT

Sorry, I just re-read your original message. I wanted to see if you could login as root via ssh or something else. I thought maybe the root account was locked.

Re: Root logon denied at console.

Court Campbell — Fri, 19 Sep 2008 16:42:10 GMT

One other thought. Try tailing /var/log/messages and /var/log/secure and see if you get any messages that might tell you what is going on.

Re: Root logon denied at console.

Adam W. — Mon, 22 Sep 2008 11:57:03 GMT

Court,
This is the error in /var/log/messages

Sep 22 08:38:48 alexandria gdm[4379]: Root login disallowed on display ':0'Sep 22 08:40:04 alexandria gdm[4379]: Root login disallowed on display ':0'
Sep 22 08:45:34 alexandria gdm[4379]: Root login disallowed on display ':0'

All entries in the /etc/secrity/access.conf file have been changes to allow root logon. I did not reboot or anything though. Root still cannot log in from the console. Should I attach a copy of the securetty file and access.conf file? Maybe I am missing something.

Re: Root logon denied at console.

Ivan Ferreira — Mon, 22 Sep 2008 12:22:41 GMT

I think that in this case, the problem is your GDM configuration.

Edit the /etc/X11/gdm/gdm.conf file and set:

AllowRoot=true

I'm not sure if gdm.conf is on that path on RH 3.0, but the file name gdm.conf must exists somewhere in /etc.

find /etc -name gdm.conf

Re: Root logon denied at console.

Court Campbell — Mon, 22 Sep 2008 12:24:46 GMT

I am not sure if this is a pam config issue. or something else. But you cannot login to gnome. You could always just hit something like alt+f2 and login.

Re: Root logon denied at console.

Court Campbell — Mon, 22 Sep 2008 12:28:09 GMT

Check your gdm.conf and see if AllowRoot=0, if not change it. Then try logging in.

Re: Root logon denied at console.

Adam W. — Mon, 22 Sep 2008 12:32:56 GMT

Court/Ivan,
THanks I will give that a shot and reply with the outcome.

Re: Root logon denied at console.

Adam W. — Mon, 22 Sep 2008 12:44:52 GMT

Court/Ivan,

There was a gdm directory in /etc so I went in and there was a custom.conf file I modified the frile from Allowroot=false to Allowroot=true. And I still cannot log in as root from the console. Sorry to keep bugging your guys, but I can't figure this out.