Controlling IPv6 Preference for traffic from the firewall itself¶
By default, pfSense will prefer IPv6 when configured. If IPv6 routing is not functional but the system believes it is, pfSense may fail to check updates or download packages properly.
To change this behavior, pfSense provides a method in the GUI to control whether services on the firewall prefer IPv4 over IPv6:
Navigate to System > Advanced on the Networking tab
Check Prefer to use IPv4 even if IPv6 is available
Once the settings have been saved, the firewall itself will prefer IPv4 for outbound communication.