[Milhouse]

it seems, that passwd does not accept weak passwords:

Yes, we've already established that - what point are you making?

Enter a "strong" password (a weak password would be something like "password" or "12345678").

Quoting from the passwd documentation page:

Code:

Then, the password is tested for complexity. As a general guideline, passwords should consist of 6 to 8 characters including one or more characters from each of the following sets:

·   lower case alphabetics
·   digits 0 thru 9
·   punctuation marks

Care must be taken not to include the system default erase or kill characters.  passwd will reject any password which is not suitably complex.

Some might argue that 8 characters isn't enough for a strong password.