Dear all,

I manually added an entry to /etc/passwd file but can no longer login to the system through telnet.

Is there any other alternative to login to the Linux machine remotely.

Your help is very much appreciated.

Many thanks in advance

Telnet is not secure as password is sent in clear-text.

You're better off with SSH, install the Openssh server or if it's already installed start the ssh server:

/etc/init.d/sshd start

You can connect from the client as given below:

ssh username@192.168.0.10

username is the user you want to login as into the remote system.
192.168.0.10 : IP address of the remote system, change yours accordingly.

digen is right about telnet, but it seems you have edited a line in /etc/passwd, first we need to know: can you log in at all? (remote through ssh or local on the terminal).
I dont see why you couldnt login through telnet, but can through ssh. They use the same file (/etc/passwd).
Maybe you accidentally removed a ':', resulting in perhaps an empty password (try that).
Remember: /etc/passwd format: Name:Password: UserID:PrincipleGroup:Gecos: HomeDirectory:Shell
Where nowadays we use 'shadowed' passwords, the 'Password' field would read 'x', for better security.
These days we dont see clear text passwords anymore in the /etc/passwd, as we should. Try the UserID as the password (for root that is '0').
If nothing helps my best bet is a boot from boot-root floppies, mount the root on a temporary mount and edit the /mountpoint/etc/passwd to make it work again.
Good luck!

Hi there,

If I could access the server I would have installed SSH and followed your instructions but unfortunately I can't.
Please note that no one can access the server anymore. The /etc/passwd file is now locked. Is there any clear way to unlock this file?

Thanks

Boot the server in single user mode and get back to us with the change that you made in /etc/passwd.

If you need more information about single user mode you can search the forums and you should find plenty of threads.

Hi there,

I've added the following line to the /etc/passwd file

:0:0::

What I've effectively done is to try to create a root user with a null username and password of '0'.

Thanks

You're going to have to take that machine down to single user mode and remove that line.

1) you don't have the correct number of fields
2) you've put 0 where the passwd should be
3) usernames can't be NULL

And so on... but no one can login until you remove that entry because you've hosed /etc/passwd.

I hope you have physical access to the machine or the phone number/email of someone who does. And if the latter case is true, blame it on vi... don't tell them you did it intentionally.

Hi There,

I am gonna try your method. It feels right.
I'll let you know of the result.

Thanks frob23.