You compiled a custom kernel with a different PF version than the one installed in your /sbin directory.
This guide explores why this error happens and how to fix it to restore your firewall's functionality. Understanding the Version Mismatch The PF firewall operates in two parts:
In some cases, third-party software (like security plugins or monitoring tools) may have replaced system files with incompatible versions. Troubleshooting and Fixes 1. Perform a Configuration "Dry Run" pf configuration incompatible with pf program version
System libraries that pfctl relies on were updated to a version incompatible with the running kernel.
Restart the PF service: service pf restart or rcctl restart pf . 4. Restore from Backup (pfSense/OPNsense) You compiled a custom kernel with a different
The actual engine that inspects and filters packets at the system's core.
If this error appears on a firewall appliance after a firmware upgrade: Navigate to . Troubleshooting and Fixes 1
If the binary itself is incompatible, you must ensure both the kernel and world (userland) are on the same version.
Before assuming the system is broken, check if the error is actually triggered by a syntax issue in your configuration file that the current version of pfctl cannot parse. sudo pfctl -vnf /etc/pf.conf
Ensure you are not mixing "stable" userland binaries with a "current" kernel (or vice versa). 3. Rebuild PF Control Tools