pf(4) as a NAT44 router – Trond's place

pf(4) is a bit optimistic with regard to how many states it can track using the defaults.

[zone: pf states] PF states limit reached

Raising the hard limits to four times the default seems better:

set limit {
  states 40000,
  src-nodes 40000,
  frags 20000,
  table-entries 800000
}