PS4:Blocking OFW Updates

With the possibility of new exploits being found on your current firmware, you can disable automatic updates to prevent your console from automatically patching any existing exploits with firmware updates.

Basic Settings

 * Navigate to Settings → System → Automatic Downloads and Uploads, and uncheck "System Software Update Files" and "Install Automatically".
 * Turn off Internet connection while in stand-by mode by navigating to Settings → Power Save Settings → Set Functions Available in Rest Mode and uncheck "Stay Connected to the Internet".

Post-exploitation

 * Navigate to Debug settings → PlayStation Network → NP Environment, and simply change np value to any other word (like block, for example). This setting stays after reboot and is a alternative to DNS. In some cases of bad kernel panics, it may get switched back to "np", so be sure to check it after some time.
 * Navigate to your exploit host and run "Update Blocker" payload. This payload will create 2 folders in /update/ called PS4UPDATE.PUP and PS4UPDATE.PUP.TEMP that prevents them being replaced with the real files (folders cannot be replaced with files with the same name or vice versa - fundamental/technical limitation). The user can also create the same folders in the same directory via FTP or PS4Xplorer and replicate the payload manually. Note that this payload only blocks firmware updates, not game updates!
 * Use Al Azif's DNS which blocks both firmware and game updates (all PS/Sony connections). Some ISPs (Interne Service Providers) will block all DNS and will not allow the user to use these DNS addresses (a quick way to check is to go to Settings → User's Guide/Helpful Info → User Guide and see if it redirects you to the exploit page). Do use the first point above if you are in that situation.
 * Do note that for both NP value switch and Al Azif's DNS, some homebrew like Patch Installer which uses Sony/PS connection to download and install retail updates will stop functioning as a result (not many homebrew are like this however). To continue using them, switch value back to NP and/or remove DNS, use the homebrew and, when done using, turn them back on.