miniupnp.tuxfamily.org

[BettySanchez]

I use MiniUPnP for port‑forwarding and NAT‑PMP on my home router. It is small daemon / library for NAT traversal and works well on many platforms.
MiniUPnP I want to host small server behind NAT, but sometimes port‑forward seems not work or mapping fail. Have you seen this issue when internal server is behind extra firewall or double NAT? I read some issues about indirectly connected internal networks in MiniUPnP (sub‑net behind router). GitHub As I also work in building/construction field my job is as “roof estimators” I wonder if maybe concept of “double layers / supports / insulation / protection” like in building structure has resemblance to double NAT + firewall layers in networking: each layer changes status or restricts access. Maybe extra firewall layer behaves like “moisture barrier” or “insulation layer.” I ask, maybe someone here with deep experience of UPnP + router + firewall + network‑layers share idea: how to ensure port‑forward reliably when network is “layered”? And any advice to test or debug such multi‑layered network. Thank you for reading I hope to learn from your experience.