Failed to bind server to: {devserver_bind_address}, is there

Error message

Failed to bind server to: {devserver_bind_address}, is there another devserver running?
To run multiple devservers, use the --port flag to specify a different port

What it means

Error "Failed to bind server to: {devserver_bind_address}, is there another devserver running? To run multiple devservers, use the --port flag to specify a different port" thrown in DioxusLabs/dioxus.

Source

Thrown at packages/cli/src/serve/server.rs:95

    /// Start the development server.
    /// This will set up the default http server if there's no server specified (usually via fullstack).
    ///
    /// This will also start the websocket server that powers the devtools. If you want to communicate
    /// with connected devtools clients, this is the place to do it.
    pub(crate) fn start(runner: &AppServer) -> Result<Self> {
        let (hot_reload_sockets_tx, hot_reload_sockets_rx) = futures_channel::mpsc::unbounded();
        let (build_status_sockets_tx, build_status_sockets_rx) = futures_channel::mpsc::unbounded();

        // Create the listener that we'll pass into the devserver, but save its IP here so
        // we can display it to the user in the tui
        let devserver_bind_ip = runner.devserver_bind_ip;
        let devserver_port = runner.devserver_port;
        let proxied_port = runner.proxied_port;
        let devserver_exposed_ip = devserver_bind_ip;

        let devserver_bind_address = SocketAddr::new(devserver_bind_ip, devserver_port);
        let listener = std::net::TcpListener::bind(devserver_bind_address).with_context(|| {
            anyhow::anyhow!(
                "Failed to bind server to: {devserver_bind_address}, is there another devserver running?\nTo run multiple devservers, use the --port flag to specify a different port"
            )
        })?;

        let proxied_address = proxied_port.map(|port| SocketAddr::new(devserver_exposed_ip, port));

        // Set up the router with some shared state that we'll update later to reflect the current state of the build
        let build_status = SharedStatus::new_with_starting_build();
        let router = build_devserver_router(
            runner,
            hot_reload_sockets_tx,
            build_status_sockets_tx,
            proxied_address,
            build_status.clone(),
        )?;

        // And finally, start the server mainloop
        tokio::spawn(devserver_mainloop(

View on GitHub (pinned to 24f6a829df)

Solutions

The devserver port is already in use. Stop the other devserver or pass --port to use a different port.

When it happens

Trigger: Thrown at packages/cli/src/serve/server.rs:95 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of DioxusLabs/dioxus@24f6a829df (2026-08-23). Data as JSON: /api/errors/5cee8330e6b0ffa9. Report an issue: GitHub.