Network isolation between services in Docker - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is network isolation between services in Docker?

Network isolation means keeping Docker containers separated so they cannot communicate unless explicitly allowed. This helps improve security and control over service interactions.

beginner

How do Docker networks help with service isolation?

Docker networks create separate virtual networks. Containers on different networks cannot talk to each other unless connected to a common network, enabling isolation.

beginner

What command creates a new isolated Docker network?

Use docker network create my_isolated_network to create a new isolated network.

beginner

How to run a container attached to a specific Docker network?

Use docker run --network my_isolated_network my_image to attach a container to the isolated network.

intermediate

Why is network isolation important in microservices?

It limits communication to only necessary services, reducing security risks and accidental data leaks between services.

Which Docker command creates a new isolated network?

A docker network new my_network

B docker create network my_network

C docker network create my_network

D docker network build my_network

The correct command is docker network create my_network to create a new network.

If two containers are on different Docker networks, can they communicate by default?

A Yes, always

B No, not unless connected to a common network

C Only if they share the same image

D Only if they run on the same host

Containers on different Docker networks cannot communicate unless connected to a shared network.

What flag attaches a container to a specific Docker network when running it?

A --net

B --link

C --connect

D --network

The correct flag is --network to specify the network for the container.

Why use network isolation between microservices?

A To limit communication and improve security

B To reduce image size

C To enable automatic updates

D To improve container startup speed

Network isolation limits communication between services, improving security.

Which Docker network type provides isolation by default?

A none

B host

C bridge

D overlay

The none network disables all networking, providing full isolation.

Explain how Docker networks can be used to isolate services and why this is useful.

Think about how separating rooms in a house can keep conversations private.

Describe the steps to create an isolated Docker network and run a container on it.

Imagine creating a private chat group and inviting only certain friends.