You can use Control Center to add, remove, or reposition host-based authentication entries in the pg_hba.conf file.
Select a Database Cluster and choose Edit => HBA. (Alternatively, double-click on a row of the HBA tab of the Detail Area.)
The Edit HBA dialog appears, displaying the current authorization entries in the pg_hba.conf file.
To modify an entry, select a row of the table and use the Edit, Delete, Move Up and Move Down buttons to establish the desired host-based authentication policy. For more information, refer to Host-Based Authentication in the PostgreSQL 7.3 Administrator's Guide.
After making the desired changes, click OK. The system verifies that the changes are valid, then, if the backend is running, causes it to reload the configuration.
The following dialogs appear when you click the Add and Edit buttons respectively.
In the Add HBA Entry or Edit HBA Entry dialog that appears, fields can be enabled or disabled depending on the Type property selected. The Mask field is automatically filled when the IP Address is changed, but you can change this default value.