UNIX for Dummies Questions & Answers

I am running a Linux Red Hat 7.2 system and I can't log into the root account.

When I tried to su to root from another user by using the command su - root, I get this error message:

su: basename.c:67: base_name:Assertion `all-slashes || !((*(p - 1)) == '/ ' ) failed

also, when I tried to log in to root account from the login prompt, I get a message saying theres an error with my account.

by the way, I am the only one in total control of this system and the system isn't connected to the internet or any network.

Help is needed as soon as possible

Perhaps you have a corrupt password file?

well, how do I fix it????

You may have to reboot to single user mode.

shutdown -ry now and stop it at the interrupt and boot to single user mode. Your shutdown command may have an option to come back to single without interruption from the keyboard.

However, since you can't loging as root. You may have to power off and back on to get to single and use the interrupt method above.

Regarding the password file.
You can do a few things. What are the permissions on your /etc/passwd file? If you can replace it with a backup of the passwd that would be good. If it is truly corrupted. You can just create a new one by hand. Perform an "cat /etc/passwd" then note the lines that are system Ids. Create a new passwd file with vi with just the system IDs.


On my OS there is another minimal passwd file that is under a subdirectory of /etc, /etc/opt/dce/passwd_override.

I don't expect yours to be in the same place, or possibly to have one of these, but it is worth a try.

If you have something like this copy it into place.

I dont get it??

How do I create a /etc/passwd file from a ordinary user. I cant use any superuser power because root is the only supreme power on my system. Now,that the root account is corrupted, I have no idea on what to do.

even if I was to create the /etc/passwd file, what do I put in it and how do I replace the original with this newly created passwd file??

if only there was a safe mode whereas I can go in the root account with minimum powers and make necessary changes then reboot

don't panic.

Please read carefully.

If you have an alternate passwd file, you can use mv to get it into place.

mv alt_passwd /etc/passwd


I want you to check the permissions on the /etc/passwd file. It may be that the permissions are such that you can edit it as a normal user. If the permissions are at least 755, you should be able to replace it with a temporary passwd file. OR Do you have another copy of the passwd file (ie passwd.orig)?

However, if that is not the case, you will have to reboot to single user mode.

IF you have one, you may have to boot with your system disk to get it to come up to single depending on if the system tries to read the passwd file.


If none of these is true, then your options are slim. You have to have one of three things for you to recover.
1) an alternate passwd file you can move into place if the permissions will allow.
2) create a new passwd file with limited users in it, system IDs only.
3) reboot to single and do #2.


If not, then you are stuck. I would suggest in the future to make a tar of your root filesystem for just such an occasion.

Sorry if this doesn't help. The last option as you probably have guessed is reload/reinstall the OS.

OK, first... answer this questions:


Do you have a password file?


You don't have to be root to see the file or to copy it...... I suggest you post the contents so we can take a look..... thanks.