73 lines
2.7 KiB
Markdown
73 lines
2.7 KiB
Markdown
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---
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title: Docker Network
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---
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By design containers are isolated from the host and other running containers. The virtual networking of Docker containers allows them to talk to services inside other containers or on the host.
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By default, every container gets a virtual Ethernet interface that gets connected via a bridge on the host.
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## List all Docker networks
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`docker network ls` lists all current Docker networks.
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When installing Docker it creates three default networks:
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- *bridge*:
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Default for containers that are run without a network specified
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- *host*:
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Allows a container to directly use the network stack of the host
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- *none*:
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No networking to other containers is possible
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You can use these, but when you plan on running your service containers in production it is advised to create special networks.
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## Inspect a Docker Network
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`docker network inspect NAMEOFNETWORK` outputs details on the configuration of the network in JSON format. For example, the containers that are part of the network, or their private IPv4-adresses.
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```json
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"Containers": {
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"156693991b505f5c17ae524ee31fe18775e62011db816cce5313cd2f22576a9c": {
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"Name": "app",
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"EndpointID": "ac4d2dff6f2191fa22749d6c00a2005f400ee74771e0e9186ffa35c94f9b9994",
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"MacAddress": "02:42:ac:18:00:02",
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"IPv4Address": "172.24.0.2/16",
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"IPv6Address": ""
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},
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"64b4328f46a7c4f26e925b66cd6783dc024a93210e958b768292427e52b35bf3": {
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"Name": "database",
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"EndpointID": "b7dcf87f8a8501eab01c6e7fe58aa9454ae81c84c3bc41d9490bcd92e2ab531a",
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"MacAddress": "02:42:ac:18:00:03",
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"IPv4Address": "172.24.0.3/16",
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"IPv6Address": ""
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}
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```
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## Create a Docker network
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To create a network simply run:
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`docker network create my_app_network`
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## Attach Containers to a network
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To directly attach a new container to the newly created network run:
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`docker run --name my_new_webapp --network="my_app_network" -d httpd:2.4-alpine`
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To attach an already running container to a network run:
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`docker network connect my_app_network my_running_webapp`
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They can now talk to each other.
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## Networking with Docker Compose
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When running your containers with Docker Compose it by default creates a network of all service containers in the `docker-compose.yml` file.
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#### For More Information:
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- [Docker Networking: Overview](https://docs.docker.com/network/)
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- [Docker Networking: Tutorial for standalone containers](https://docs.docker.com/network/network-tutorial-standalone/)
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- [Docker Compose: Networking in Compose](https://docs.docker.com/compose/networking/)
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