High Availability Sync is the feature that pfSense uses to synchronize configuration from a Master to a Slave, transferring configuration setup over one chosen interface.

On the Master, go to System > High Availability Sync.

  • Check the box “Synchronize States”,
  • Choose the interface through where the configuration will be transferred,
  • Insert the IP of the Slave in “Synchronize Config to IP”,
  • Type username and password of the administrator or any other user with enough privileges,
  • Check the box “Taggle All” to allow full synchronization,
  • Then “Save”.

At this point, you should create one user and see if it will be copied to the slave. Suggestion: create one user called ‘sync’ that will be used only for this reason.

On the Master, go to System > User Manager.

  • Click in “Add”,
  • Define “Username” and “Password”,
  • In “Effective Privileges” click in “+ Add”,
  • In “Assigned Privileges” mark only “System – HA node Sync”,
  • Then “Save” and “Save”.

On the Slave, go to System > User Manager and check if the user ‘sync’ is there.

On the Master, go to System > High Availability Sync and replace the user ‘admin’ with the ‘sync’ and its password.

Remember, all the configurations you do on the Slave will be overwritten by the master configuration.

If the system notice did not give any alert, everything is fine and working.