By default, the passwd command assumes a minimum length of six characters. You
can use the PASSLENGTH
default in the /etc/defaults/passwd file to change that by setting the minimum number of characters that a user's password must
contain to some other number.
To set the minimum number of characters to something other than six, type the appropriate number of characters after the equal sign on the PASSLENGTH= line:
PASSLENGTH=N |
Where N is a number of characters. For example, PASSLENGTH=7.