Microservices in the real world

A single application that houses multiple features, often as a single binary, making it difficult to scale or modify individual parts.

A software design approach where an application is broken down into smaller, independent services, each responsible for a specific feature.

A self-contained unit of code that runs a specific feature of an application, typically deployed as a container.

A lightweight, portable software package that bundles an application with its dependencies, allowing for easier deployment and scaling.

The act of updating or patching a specific feature of an application without affecting other parts, which is easier in a microservices architecture.

Scaling a specific feature of an application by increasing the number of instances of the corresponding microservice, without impacting other features.

The process of deploying, managing, and monitoring microservices in a production environment, often using cloud platforms and tools.

A distributed system where microservices communicate with each other over a network to function as a single application.

A collection of one or more Docker hosts that work together to provide high availability and scalability.

A single machine in a Docker Swarm Cluster.

A node responsible for running containers and applications.

A node responsible for managing the cluster's state and scheduling containers.

The intelligence of the Docker Swarm Cluster, responsible for tasks like scheduling and storing cluster data.

Enables features like updating, patching, and auto-scaling individual microservices without affecting the rest of the application. It's great for managing complex applications.

A configuration file that defines the infrastructure and microservices for an application, including networks, volumes, and services.

A platform that reads and interprets a compose file to build, deploy, and manage the defined microservices and infrastructure.

A type of application where there are multiple microservices (containers) working together to fulfill the application's functionality. Consider it an application with several parts interacting.

A method of deploying and managing applications by defining all aspects in a configuration file, such as networks, volumes, and services.

A persistent storage space that can be shared between containers.

A virtual network connecting containers within a multi-container application.

The code responsible for building a container image. It describes the steps and instructions for building the image.

A simple web application that increments a counter upon each page refresh and stores the count in a Redis cache.

A software used for caching data, providing faster access times for frequently accessed information. In the counter application, it stores the counter value for quick retrieval.

Mapping a specific port on the container to a different port on the host machine. It allows access to the service within the container from the host machine.

Attaching a volume to a container. This allows the container to access the volume's data and persists the data even after the container stops.

A Docker Swarm node that runs applications and containers, while the manager node manages the cluster.

A Docker Swarm node responsible for managing the cluster's state, scheduling containers, and handling orchestration tasks.

The command used to create and manage Docker services in a Swarm cluster.

An object in Docker Swarm that defines a service and manages its deployment, scaling, and orchestration.

A command line interface tool for Docker Swarm used to manage Docker services.

A type of service deployment in Docker Swarm that allows for zero downtime deployments and rollbacks.

The ability of a service to automatically revert to a previous working version if a new one is faulty.

When a manager node is only used for cluster management and not for running applications.

The Docker CLI command used to list running containers on a Swarm node.

The Docker CLI command used to view a list of running containers across all nodes in a Swarm cluster.

The ability for a service to distribute the workload across multiple containers, ensuring availability and resilience.

The feature in Docker Swarm that allows accessing a service on any node in the cluster, directing traffic to the correct container.

A web technology that allows running programs on a remote server, making applications accessible over the internet.

Creating services and configurations using a YAML file and deploying them with a single command.

A process that monitors a Docker Swarm cluster, comparing the desired state to the actual running state of services and nodes to ensure consistency and functionality.

A Docker Swarm command used to deploy and manage multi-container applications defined in a declarative YAML file.

A collection of Docker hosts that work together as a single unit, offering scalability and high availability for your applications.

A Docker command used to scale the number of replicas (instances) of a service, allowing to adjust the service's capacity as needed.

A Docker Swarm feature responsible for monitoring and maintaining the desired state of the cluster, ensuring consistent functionality even during disruptions.

A Docker Swarm feature that dynamically increases or decreases the number of running containers of a service to match the desired state.

High Availability (HA) ensures that applications remain accessible even if one or more nodes in a Docker swarm fail. This is achieved by having multiple manager nodes and spreading them across different availability zones.

In a Docker swarm, a majority of manager nodes must be operational for the swarm to function properly. If a node fails, the remaining managers will elect a new leader and the swarm will continue functioning.

Docker Swarm uses a token based authentication system to allow new nodes (managers or workers) to join the cluster and automatically verify their authenticity and access permissions.

A Docker swarm can be configured to use a specific network address for communication between its nodes. This helps centralize communication and ensures proper routing within the cluster.

Multipass is a tool used to create and manage lightweight Ubuntu Virtual Machines (VMs) that provide a cloud-like environment on different operating systems. This allows for easy testing and development of containerized applications.

Play with Docker provides a web-based environment for running Docker containers and experimenting with Docker Swarm. This is a convenient alternative to running a local setup, especially for beginners.

Docker Desktop is a software application that allows you to run Docker containers and manage Docker Swarms directly on your local machine, without setting up a virtual machine.

Docker Desktop, when running on your computer, utilizes a VM in the background to provide the Docker environment. This allows for a simplified user experience, with the VM running and managing all Docker related operations.

Docker version command displays the version of the Docker engine running on a specific node. This helps you verify that you have the correct Docker version for your swarm setup.

docker swarm init command initializes a new Docker swarm cluster by designating the node it's run on as the first manager node. This command also generates a token used for adding other manager nodes.

The docker node ls command is used to list all nodes in a Docker swarm cluster, providing details about each node's role (manager or worker), status, and current leader.

Docker Swarm commands are used to manage and interact with a Docker Swarm cluster, including adding nodes, deploying services, and managing container orchestration.

A command used for inspecting the services of an application that was deployed using Docker Swarm.

Replicas are identical containers running the same service. This allows for horizontal scaling and increased resilience. The deploy: replicas field in a Docker Compose file specifies the number of replicas.

A change in the desired state of a microservice, like scaling up or down replicas, is detected and enforced by the Control Plane. This ensures the application is always aligned with the configuration.

A simple application used in the demonstration that increments a counter on every page refresh.

A mechanism to ensure that changes are applied correctly, like scaling a service, by modifying the configuration files and then re-applying them to the swarm.

The practice of making changes to the configuration files and re-applying those changes to the swarm to update an application.