1. Name

2. Synopsis

usermod [options] LOGIN 

3. Frequently used options

-e, --expiredate EXPIRE_DATE
      The date on which the user account will be disabled. The date is
      specified in the format YYYY-MM-DD.
-L, --lock
      Lock a user’s password. This puts a ’!’ in front of the encrypted
      password, effectively disabling the password. You can’t use this
      option with -p or -U.
-U, --unlock
      Unlock a user’s password. This removes the ’!’ in front of the
      encrypted password. You can’t use this option with -p or -L. 

4. Examples

# usermod -L linuxcofnig 

Now we can try login with user linuxconfig and see if that works:

With a -U option we can unlock account:

# usermod -U linuxcofnig 

# grep linuxconfig etc/shadow | head -c 15 |  sed -e 's/$/\n/' 

# usermod --expiredate 2010-01-01 linuxconfig