(We’re doing port 5000 specifically because that’s where our Docker image is listening, Flask’s default port. p 8080:80 would redirect traffic from port 8080 on all interfaces in the main network namespace to port 80 on the container’s external interface. To break it down explicitly: -p 5000:5000 means redirecting traffic from port 5000 on all interfaces in the main network namespace to the container’s port 5000 on its external interface. If we run docker run with -p 5000:5000, it will forward from all interfaces where the Docker daemon is running (for our purposes, the main network namespace) to the external IP address of the containter. Docker run port-forwarding (is not enough) Instead of connecting the networks, you need features to handle the various aspects of application communication.
![network connect app network connect app](https://consumer-tkbdownload.huawei.com/ctkbfm/servlet/download/downloadServlet/H4sIAAAAAAAAAD2PTU_DMBBE_4vPpdqNd03MCaeOVS6IQzlXTuwES21a5aMIEP-dpIo4jvQ0b-ZHTEPsD1_XKJ4Eio0Il89ujXKOTTrFV39eYuwepuGYzr6NR0CdAWaPUm-vXbtyb378mLmqgQA11qrOiRrlK4lBeR2aILnxCDNdpe-XMKN783xvBVCaFC_Cuo9-TJfukBYpKtAkgQABYCOG1HZ-nPpljttZZuWglFRkwLlkk2tpnDZsLeiCHBnkzEqHlnYlkWbUlKMrubCSaXbd_CmF9___Yz_F-7b1_96I3z-NEE7tIAEAAA%3D%3D.png)
Because there are many different customers in the same App Service scale unit, you can't connect the App Service network directly to your network. How do we connect the two network namespaces? With Docker port-forwarding. All the roles in an App Service deployment exist in a multitenant network. The browser is connecting to 127.0.0.1 in the main, default network namespace.īut those are different interfaces, so no connection is made. Now it’s clear why there’s a connection refused: the server is listening on 127.0.0.1 inside the container’s network namespace. The resulting network setup looks like this: Your operating system has multiple network “interfaces”.įor example, on my computer (with output shortened for clarity): Docker runs on non-Linux OSes like macOS by running a Linux virtual machine, but the practical consequences are the same.
![network connect app network connect app](https://c8.alamy.com/comp/2EM70GW/satellite-connection-cloud-data-infrastructure-vector-illustration-ux-ui-onboarding-mobile-app-page-screen-set-with-line-datacenter-server-digital-technology-wireless-signals-connect-to-network-2EM70GW.jpg)
I’m going to assume the main OS is Linux, for simplicity of explanation. Let’s start with our first scenario: you run a server directly inside your operating system, and then connect to it.
![network connect app network connect app](https://www.mariecuriealumni.eu/sites/default/files/inline-images/lQPnFIdPjjXJ1CqobDLoB0GPohu4TiDyGi5Yv4NhZujNkLY7zk.jpg)