Do not worry; this error is generally straightforward to fix by updating your configuration file to match the new syntax. 1. Identify the Exact Conflict
Before you can fix the problem, you need to confirm the root cause.
freebsd-update fetch freebsd-update install # Rebuild any third-party modules if necessary shutdown -r now pf configuration incompatible with pf program version
kldunload pf
Sometimes, the kernel holds onto old rule structures in memory that conflict with a newly updated pfctl binary structure. To clear out the memory tables and perform a fresh, clean load, follow this sequence: First, completely disable the Packet Filter subsystem: sudo pfctl -d Use code with caution. Do not worry; this error is generally straightforward
Legacy PF rules required explicit state keeping definitions like keep state or modulate state . Modern PF implementations keep state by default on all pass rules, and some explicit flags have changed. pass out on ext_if proto tcp all keep state (flags S/SA) Use code with caution. Modern Correct Syntax: pass out on ext_if proto tcp all Use code with caution. 3. Removal of nat-to and rdr-to Syntax Variants
This public link is valid for 7 days and shares a thread, including any personal information you added. This link or copies made by others cannot be deleted. If you share with third parties, their policies apply. Can’t copy the link right now. Try again later. Modern PF implementations keep state by default on
Note: You may need to run this command multiple times—once after fetching updates, once after the first reboot to update the kernel, and a final time to update user-space applications. Step 3: Synchronize Custom Builds (Source Upgrades)
The error message occurs when your operating system's Packet Filter (PF) firewall tool reads a configuration file ( pf.conf ) that uses rules, syntax, or options your current software version does not support. This guide explains why this happens and how to fix it. Why This Error Happens