This post will cover topic related to ‘How to Manage Kubernetes Networks’ with multiple docker command examples and different scenerios. So this will help you to understand the command docker and options available in it. Also this post will explain you how to use docker command.
Docker provides powerful networking capabilities that are essential when managing Kubernetes clusters. The docker network command allows you to create, manage, and inspect networks within Docker, which are fundamental for communication between containers and other entities in a Kubernetes environment.
Here are several examples demonstrating the usage of docker network:
Example 1: Create a Bridge Network
To create a bridge network named my-bridge-net, use the following command:
docker network create my-bridge-net
This command creates a new bridge network that containers can connect to for internal communication.
Verification: Verify by listing all networks: docker network ls. Look for my-bridge-net in the output.
Example 2: Inspect Network Details
To inspect details of the network my-bridge-net, use:
docker network inspect my-bridge-net
This provides detailed information about the network configuration, including subnet details and connected containers.
Verification: Check the output for configuration details like subnet range and gateway.
Example 3: Connect a Container to a Network
Connect an existing container named web-container to my-bridge-net:
docker network connect my-bridge-net web-container
This allows web-container to communicate with other containers on the my-bridge-net network.
Verification: Check network connections of web-container using docker network inspect my-bridge-net.
Example 4: Disconnect a Container from a Network
Disconnect web-container from my-bridge-net:
docker network disconnect my-bridge-net web-container
This removes the container from the specified network, isolating it from other containers on that network.
Verification: Ensure web-container no longer appears in the network’s list of connected containers.
Example 5: List Networks
To list all Docker networks on the host:
docker network ls
This command displays a list of all networks, including their ID, name, and driver.
Verification: Check the output for a comprehensive list of networks available.
Example 6: Remove a Network
To remove the my-bridge-net network:
docker network rm my-bridge-net
This command deletes the specified network, disconnecting all containers attached to it.
Verification: Confirm the network deletion by attempting to inspect or list it again.
Example 7: Create an Overlay Network
Create an overlay network for multi-host communication:
docker network create --driver overlay my-overlay-net
This creates a Docker overlay network that spans across multiple Docker daemons.
Verification: Ensure the overlay network appears in the output of docker network ls.
Example 8: Connect Service to Overlay Network
Connect a Docker service named db-service to my-overlay-net:
docker service update --network-add my-overlay-net db-service
This command attaches db-service to the overlay network, enabling cross-node communication.
Verification: Verify network attachment using Docker service inspect commands.
Example 9: Create a Macvlan Network
Create a Macvlan network for containers with direct host-like connectivity:
docker network create -d macvlan --subnet=192.168.1.0/24 --gateway=192.168.1.1 -o parent=eth0 my-macvlan-net
This command configures a Macvlan network that allows containers to have their own MAC addresses.
Verification: Check the network configuration details using docker network inspect my-macvlan-net.
Example 10: Connect Container to Macvlan Network
Connect a container named app-container to my-macvlan-net:
docker network connect my-macvlan-net app-container
This connects app-container to the Macvlan network, enabling it to communicate directly with the host network.
Verification: Verify connectivity and IP assignment of app-container using network inspection commands.
Also check similar articles.
How to Manage Kubernetes Image Manifests
How to Manage Kubernetes Images
How to Manage Kubernetes Contexts
How to Manage Kubernetes Containers
How to Manage Kubernetes Container Checkpoints
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