DoorStop X Firewall
User's Guide

Welcome to the DoorStop X Firewall, from Open Door Networks, developers of the Mac's original firewall (DoorStop for Mac OS 8.1). With the DoorStop X Firewall you can quickly and easily secure your Mac against undesired access from the Internet. You can also learn about important aspects of Internet security in general, through the firewall's integration with other components of the DoorStop X Security Suite, such as our book, Internet Security for Your Macintosh and iPhone. Chapter numbers and section names of relevant passages from this book are indicated throughout this User's Guide in blue italics.

About version 2.4

In Summer 2011 Apple introduced Lion (Mac OS X 10.7) and iCloud, a seamless way of accessing your content over the Internet from all your devices. Both Lion and iCloud have significant ramifications on the security of your Macintosh and other Apple devices. Lion, now shipping, makes significant changes to some of the underlying OS X system infrastructure, in particular various security settings. These changes affect the DoorStop X Firewall in a major way, so we've created version 2.4, which is required to run effectively on Lion. Most components of iCloud, on the other hand, were not made available at the time of the initial Lion release and an in-depth analysis of its ramifications on Internet security was not possible. Thus the book ("Internet Security for Your Macintosh and iPhone") that is built into DoorStop X has not yet been changed, pending iCloud's availability and our subsequent analysis. Likewise the advice in our Who's There? Firewall Advisor has not been updated. DoorStop and Who's There? remain integrated.

NOTE: if you are installing DoorStop on a multi-user Lion machine, be sure to see the important caveat.

Table of Contents
Getting Started
  • System requirements
  • DoorStop X & other firewalls
  • Installation
  • Lion and multi-user machines
  • Upgrading
  • Quick start
  • Online Help
  • Purchasing DoorStop X
  • Entering a serial number
  • Related products
DoorStop X Basics
  • Key concepts
    • IP addresses
    • Ports
    • Packets & protocols
  • Using DoorStop X
Protecting Basic Services
  • The setup window
  • Protecting a service
  • Editing and deleting built-in service entries
  • Adding an address to a service's address list
  • Changing/deleting an address in a service's address list
  • Further information about a service
User-defined Services
  • The setup window
  • Creating a new service entry
  • Duplicating user-defined service entries
  • Editing & deleting user-defined service entries
  • Custom icons
  • Further information about a service
Configuration Tips
  • File Sharing
  • iApps and OS X's built-in firewall
  • iChat
  • iTunes
  • iPhoto
  • Apple Remote Desktop
  • Internet Sharing
  • FTP clients

Accessing the Book, the Blog & Twitter


  • Browsing
  • Information on a specific service
  • The standalone version of Internet Security for Your Macintosh
  • Logging overview
  • Setting logging defaults
  • Setting service-specific logging
  • Log file details and archiving
  • Resetting the log file
  • Viewing the log file
Advanced Topics
  • UDP protection
  • Stealth mode
  • IPv6 protection
  • Turning off Tool Tips
  • Using the status icon
  • Locations
  • Testing DoorStop X
  • What clients will see
  • Uninstalling DoorStop X
  • Update information
  • Common problems & their solutions
  • Notes on installation
  • TCP & UDP port numbers
  • Log file format
  • Sample log lines
  • Reading the log file
  • DoorStop and multiple users on Lion

This entire User's Guide is copyright (C) 2000-2011 Open Door Networks, Inc. DoorStop X is a trademark of Open Door Networks, Inc. All other trademarks are owned by their respective companies.