Click on the Limits and Access Control icon on the module's main page to open the form shown in Figure 41.4.

Each row in the Deny access from table specifies an IP address, hostname, or pattern from which block logins. As with other tables in this module, there will always be an additional empty row for adding a new restricted address.

In the Deny from address field, you can also enter the full path to a file containing banned addresses, using negated patterns like !192.168.1.*, or even the special address !nameserved, which matches all clients that do not have a valid reverse DNS address. Only one can be entered, however—to block additional addresses, you will need to add more rows.

In the Error message file field, you must enter the full path to a file containing a message that will be sent to blocked clients. This should explain to connecting users that they have been blocked, and perhaps give a reason why.

If you want to add more than one row, you will need to save this form and reopen it so that a new empty row appears at the bottom of the table. Existing restrictions can be edited by just changing their fields, or deleted by clearing out the address.

When you are done, hit the Save button at the bottom of the form to activate the new address restrictions.