How to Change Passwords and Password Policy in Lion Server's Server App
The Server app’s Users pane in Lion Server provides two types of password management. First, you can manually change a password for a user account. To do this, simply select a user from the Users list, click on the gear icon, and select Reset Password from the pop-up menu. Next, type a new password, type the password again to verify, and click the Change Password button.
The other thing you can do is create a password policy that applies to all user accounts. Again, click on the gear icon under the Users list, but this time, select Edit Global Password Policy. A dialog appears, presenting a dozen policy settings, all of which are turned off by default.
You can create requirements for passwords, such the minimum number of characters. You can require that new passwords be different from previous passwords or that they be different from the account name. You can disable login after so many failed attempts or a period of inactivity, or you can have it expire on a certain date. Remember, though, that these policies apply to all users.