Stardew Valley Proxy: Hosting, Router Rules and Closed Ports

In farming games, the network side is usually noticed late, because when you play alone the game has little to say to the outside world. The moment a second player joins, the picture changes: there is now a relationship in which one side listens and the other connects, and that relationship can easily break depending on which network you are on.

The sections below seek answers to three questions. In co-op, whose machine exactly is the connection made to? What changes if you write the proxy rule on the gateway instead of the device? If a connection cannot be established on a campus or office network, is the game responsible, or the outbound filter?

Let us draw a boundary from the outset: a forward proxy is a routing decision for outbound connections. It does not accept incoming connections, it does not expose your machine to the outside, and it does not automatically cover the whole in-game stream.

Who is the co-op connection actually established between?

When you play alone, the game's network needs are next to nothing; the main component talking to the outside is the client of the platform you play on. Cloud save sync, achievements and the friends list are that client's job, and they work even when the game process is closed. That is why some of the problems described as "the game will not connect to the internet" are actually the platform client's problem.

In co-op, one player hosts the farm. That machine is the game's authority: the flow of time, crop state and inventory are kept there, and the other players get what they see from it. Joining happens in two different ways, and the two do not behave the same way with a proxy. The first is the platform's friends list or invite mechanism; the second is connecting directly to the host's address.

On the invite route, establishing the connection is delegated to the platform's own network layer. That layer chooses its own transport method, flows through an intermediate relay when needed, and does not resemble the HTTPS request–response pattern you are used to in a browser. A HTTP proxy rule defined on the system should not be expected to cover this flow.

When joining by direct address, the client tries to reach the host's public IP address and a specific port. What matters here is not your exit but the NAT and firewall configuration on the host's side. If the host is behind CGNAT, they have no directly reachable address from outside and the connection cannot be established no matter what you do.

Who is hosting the farm: the host machine and community solutions

Hosting sitting with one of the players has two consequences. The first is persistence: while the host is offline the farm is unreachable too, because the copy of the world is on that machine. The second is load distribution; the host's line and processor determine how smooth the session is for everyone. That is why, in a group of friends, having the person with the best connection host makes more difference than any proxy setting.

The route communities take to get around this limit is to run the game on a machine that is always on. An instance running continuously on a rented server or an old computer at home removes the dependency on the host's availability. This is a hosting decision, not a proxy decision; confusing the two is the most common conceptual error in the field.

Let us make the distinction clear. A forward proxy passes your outbound requests through an exit. It does not listen for incoming connections and forward them to you, and it does not publish your machine to the internet. The component that handles inbound traffic is the architecture facing the other way; the difference is in the forward proxy versus reverse proxy comparison in detail.

The practical result is this: if you are the host, your proxy exit will not enable your friends to reach you. A proxy takes on meaning when you are the joining party and the protocol it carries is suitable. On the hosting side, what needs solving is the address's reachability from outside and whether the port is open.

Should you write the rule on the device or on the gateway?

A proxy is a routing rule, and the rule's scope is equal to where you write it. When you write it in the operating system setting, compatible applications on that machine are affected. When you write it in a browser profile, only that profile is affected. When you write it at the gateway level, every device on that network is routed to the same exit.

Most home routers do not come with a built-in proxy client; the "proxy" tab you see in the interface usually concerns management access on the WAN side. If you want network-wide routing, either the router must support alternative firmware or there must be a separate device on the network acting as the gateway. Setup options and their limits are using a proxy via the router article.

The attractive side of the gateway approach is that it also covers devices with no proxy field of their own. The cost is difficulty of diagnosis: when a problem arises, it becomes harder to isolate which device's flow is affected, and everyone at home experiences the same outage. During testing, keeping the rule on a single machine first and then widening the scope is a safer order.

Where do you start if a connection cannot be established on a campus or office network?

Corporate and campus networks squeeze outbound traffic into a narrow corridor. In the common configuration, only the two ports used for the web are open, the remaining destinations are closed, and UDP is mostly not passed at all. This policy is not specific to games; update services, video conferencing tools and remote desktop solutions hit the same wall.

Start the diagnosis by isolating the symptom. Does the game not open at all, or does it open but the co-op session fails to establish? The first concerns the platform client's login traffic and usually flows over HTTPS. The second concerns the game session's own transport, and this is the part most affected by filters. If you get the same result on a second device on the same network, the problem is not on your device, it is on the network.

The right step is not to force the filter but to look for a path compatible with the network policy. On a corporate network, telling the network administrator in writing which destinations and which ports you need produces results far faster than settings tried by guesswork. A breakdown of typical restrictions on campus networks is access restrictions on school and workplace networks .

A proxy is no magic key in this picture; it only offers an alternative route for the protocols it can carry. Parts that flow over TCP, such as platform login, the store and patch downloads, can pass through an exit. If the game session's own stream uses UDP and the network does not pass UDP, defining a proxy will not make that part work.