Linux passwd command

**gvBlake** · 13-01-2009

When I try to modify an existing account as root I get the following:

#passwd Blake
Changing password for user Blake
New password:
Retype new password:
passwd: Failed preliminary check by password service

What might be causing this problem?
The user was created using the create-account command.

**Calvin K** · 13-01-2009

Is the password long enough to be accepted? A 4 digit password is rather weak. I would expect a more informative message though, if that were the case.

**Lillebror** · 13-01-2009

Old passwd from redhat (maybe that's the one you use) had a nice option -N just for this purpose. Read passwd man page for details.

**SalVatore** · 13-01-2009

Using the explicit name "root" shouldn't have changed anything. I would also guess that PAM might be enforcing some strict password checking here.

**MrChris-** · 13-01-2009

If your old NIS based password was longer then 8 characters and was set with an older version (RH6.2 for example) it does give you an authentication failure with RH7.2. Resetting the password with the yppasswd command (to the same string) seems to fix the problem.

**Solomon** · 13-01-2009

By Default the minimum password length is 5 characters. This can be changed but is not recommended. Try a password at least 5 characters. You could get into the shadowed password files and change it manually to a shorter password, but we won't go there, as it can corrupt your entire user file.