Problems with chpasswd

dcarrington · 04-23-2015, 05:59 PM

I'm not sure what I'm doing wrong...everything I've found indicates that I'm doing this correctly.

I have a file, password.txt, with the following contents:

Code:

root:Password1

I run 'chpasswd < password.txt' and I get no errors. When I run 'll /etc/shadow' I can see the timestamp has been changed on my shadow file.

My previous password no longer works, but when I try to log in as root using the new password, it fails.

Code:

$ su -
Password:
su: incorrect password

What am I missing?

dcarrington · 04-23-2015, 06:29 PM

I've found a workaround that looks like it will work, but I'm still confused as to why my chpasswd command doesn't work properly.

The workaround is to change the password.txt file to contain ONLY the password and then run

Code:

cat password.txt | passwd --stdin root

That seems to work correctly.

astrogeek · 04-23-2015, 06:36 PM

Not sure why chpasswd is not working, I have never used it. But you might check that the default encryption method is defined in the environment variables or in /etc/login.defs.

But I am curious why you need to use the password from a file if only changing the root password?

chpasswd man page states that it is intended for bulk processing of many user passwords, and passwd would be much easier used without cat-ing the file to stdin. Which is not to say that either should not work this way for a single password.

dcarrington · 04-23-2015, 06:46 PM

Mainly because I have to change the root password on about 160 servers using a remote command function from Red Hat Satellite.

Unless there's a better way to do it, but we don't have Puppet or Ansible or any of those tools that could probably make this a lot easier.

Thanks for the reply!!