Simplifying Software Architecture Like a Superhero

A Lightweight Approach to Building Microservice Systems with Docker Swarm in a Clustered Environment

I. Introduction

II. Software Architecture Fundamentals

III. Lightweight and Simple Stack

IV. Orchestration with Docker Swarm

V. Orchestration with Docker Swarm supported by the Superhero Tool Chain

VI. Designing Software for a Clustered Environment

VII. Last Gasp

Introduction

Explanation of the Book’s Purpose and Scope

Overview of a Lightweight Approach to Software Architecture

Software Architecture Fundamentals

Brief Introduction to Software Architecture

Software architecture is the process of designing and defining the structure and organization of a software system. It involves taking decisions about the system’s components, their structure, their behavior, and the communications with external systems.

Most common architectural pattern for software systems, willingly or not, has ended up as a monolithic architecture, where the entire software system was designed and built as a single, unified entity. All or most components of a monolithic system is tightly coupled, making it difficult to modify or scale individual parts of the system. This monolithic approach makes it challenging to build software systems that can adapt to changing business needs and user requirements.

To address these limitations of monolithic system design, several new architectural patterns has been developed, and that can be used to break up the monolith into smaller, more manageable components; more decoupled.

Layered Architecture

One such pattern is the layered architecture, where the system is separated into layers, with each layer performing a specific set of functions, related to a sertain type of logic. This allows for easier maintenance and scalability of individual layers.

Microservices Architecture

Another popular pattern is the microservices architecture, where the system is broken down into small, independent services that can be developed, tested, and deployed independently of one another. This allows for greater flexibility and scalability, as well as easier maintenance and updates.

Event-Driven Architecture

A third pattern is the event-driven architecture, where the system is designed around events and their handlers, with events triggering actions and responses throughout the system. This allows for greater flexibility and responsiveness, as well as easier integration with external systems.

Boundaries in Software Architecture

Beyond adopting different architectural patterns, software architecture is about defining the structure and organization of a software system. This involves drawing boundaries between different components of the software system, regardless of the architectural approach taken.

The purpose of these boundaries is to minimize dependencies between components and to provide a meaningful and understandable organization of the system. To achieve this, the boundaries should reflect the logic of the implementation and the business domain, and be designed to provide context and a semantic meaning that is understandable to humans.

Minimizing dependencies between components helps to reduce coupling, making it easier to modify or replace individual components without affecting the rest of the system. At the same time, organizing components into meaningful and understandable boundaries makes the system more comprehensible to developers and other stakeholders, which can improve the system’s maintainability and further development.

To draw boundaries effectively, it’s important to consider the context of the system and the specific needs of the business domain. This may involve identifying components that have distinct responsibilities or that operate in different domains. It’s also important to identify and focus development on the core domain of the system - the part of the system that provides the most value to the business.

By prioritizing the core domain, developers can focus their efforts on building the system components important to the business, while also reducing the complexity and maintenance burden of less important components that can be outsourced or generalized by some standard tool or service.

In summary, drawing boundaries between components is an essential aspect of software architecture that helps to minimize dependencies and provides structure, organization and a contextual meaning.

The Foundation of a Lightweight Ecosystem

A lightweight ecosystem offers several advantages as the foundational system design approach. By focusing on the specific needs, a lightweight ecosystem requires less configuration and fewer resources, though it also comes with the prize of lacking flexibility. In this chapter, we’ll explore some of the foundational components of a lightweight ecosystem that will be covered in this writing, and why they’re essential to the stack talked about in this writing.

Docker Swarm: A Lightweight Container Orchestration

One essential component of a lightweight ecosystem is a container orchestration software. Docker Swarm is an excellent choice for this purpose, as it’s lightweight and fast. Docker Swarm is an independent piece of software that uses plugins for modularized surrounding functionality that can be used to advance settings, or chose to opt out and keep things simple. Additionally, Docker Swarm acts as the backbone manager to a clustered solution, allowing hosting of an orchestrated clustered solution, making it an ideal choice for designing a lightweight ecosystem.

Redis: A Lightweight Persistence Layer

Another important layer of an ecosystem is the persistence layer. Redis is a great option for this purpose, as it’s lightweight, fast, and flexible. It offers a joined memory space between replicated services, which is often utelized in clustering. Additionally, Redis supports clustering, making it an excellent choice for a system with high availability requirements.

Lightweight and Simple Stack

As a buisness grows and scales, one of the more significant challenges it faces is often managing its software infrastructure. Larger and more complex systems require more people to manage them, which can be costly and time-consuming. This is where the benefits of a lightweight, less flexible system architecture makes itself known.

By designing a lightweight system architecture, businesses can drastically reduce their maintenance needs. This is because a lightweight architecture is simpler and more straightforward, with fewer parts and less configurations. As a result, it requires less maintenance and fewer people to manage it, becouse there is less states to know about, monitor and trace.

One of the key benefits of a lightweight system architecture is its simplicity. By keeping things simple, businesses can avoid the complexities that come with larger, more complex systems. This, in turn, reduces the need for specialized knowledge and expertise, which can be costly to acquire and maintain. By keeping things simple, businesses can reduce their reliance on specialized expertise and focus on building a more agile and efficient team.

Introduction to the Superhero Tool Chain

The Superhero Tool Chain is a set of tools and services that have been designed to help developers meet the high expectations of modern businesses. The name Superhero was chosen because it reflects the unrealistic expectations that many businesses have of their developers. The Tool Chain was developed to make it possible to meet these expectations and turn developers into superheroes.

Why use the Superhero Tool Chain instead of more established tools on the market? The answer is simple: if the Tool Chain meets your specific needs, you’ll have less work configuring and less overhead processing. Many established tools on the market have a one-size-fits-all approach that may not meet the specific needs of your business. By using the Superhero Tool Chain, you can ensure that you have the tools and services that meet your specific needs, which means less time configuring and less overhead processing.

One of the primary focus areas of the Superhero Tool Chain is to keep it simple. The tools and services are designed to be straightforward, which means you can spend more time developing and less time figuring out how to use the tools. Additionally, the Superhero Tool Chain is built using the same frameworks as the rest of the stack, which means it’s easy to integrate and maintain.

The Superhero Tool Chain includes several different tools and services, including the Superhero Deployment service, the Superhero Reversed Proxy service, and the Superhero Eventsource service. Each of these tools and services is designed to help developers meet the high expectations of modern businesses.

Components of the Superhero Stack

The Superhero Stack is composed by services offered by the Superhero Tool Chain.

Superhero Deployment Service: Lightweight CI/CD Flow

The Superhero Deployment service is a choice to utelize to accomplish a custom CI/CD flow. It’s lightweight, flexible, and supports deployment to the clustered ecosystem. The service is independent and written using the same frameworks as the rest of the stack, which makes it easy to understand and maintain.

Superhero Eventsource Service: Lightweight Persistence Layer

The Superhero Eventsource service is often utelized by systems utelizing the Superhero Tool Chain. It’s lightweight and fast. It’s a facade service to the redis streams, required by the Superhero Eventsource client solution. The solution supports clustering and was built with transparancy for tracability in mind.

Superhero Reversed Proxy Service: Routing and SSL Management

The Superhero Reversed Proxy service is a choice for managing SSL encryption and the upstream routing to the hidden services in the the clustered environment. It offers a solution where the SSL encryption of the comunications to and from the stack can be managed by a single shard. The solution is also lightweight, fast and transparent for better monitoring.

Benefits of Using a Lightweight and Simple Stack

A lightweight and simple stack can provide numerous benefits to software developers and businesses. By focusing on the specific needs of the business, a lightweight stack can offer advantages over a more flexible and complex software stack.

One of the primary benefits of a lightweight stack is that it requires less configuration and fewer resources to set up and maintain. This can result in significant cost savings for businesses, particularly those operating on tighter budgets in a competitive market.

In addition, a lightweight stack is often easier to scale than a more complex software stack. Because it is designed with simplicity in mind, a lightweight stack is typically more flexible and adaptable to changing business needs. This can help businesses to respond quickly to new opportunities or challenges, without the same risk of suffering from time-consuming modifications to the solution.

Another benefit of using a lightweight stack is that it can reduce the risk of errors and software defects. Because the stack is simpler and more specific, there are fewer opportunities for bugs or misconfigurations. This can help businesses to ensure that their software systems are reliable and performant, minimizing the risk of unexpected disruptions.

Finally, a lightweight stack can help businesses to stay focused on their core competencies and business goals. A lightweight stack allows developers and business leaders to stay focused on what really matters - delivering value to customers and driving business growth.

Orchestration with Docker Swarm

If you have used docker before, then docker swarm is not going to be a problem.

Introduction to Docker Swarm

Docker Swarm is a container orchestration software that allows developers to manage and deploy a cluster of Docker hosts. With Docker Swarm, developers can easily create and manage containerized applications that are distributed across multiple hosts, making it an ideal tool for building and deploying microservices architectures.

One of the key features of Docker Swarm is its support for clustering. With Docker Swarm, developers can create clusters of Docker hosts that work together to manage and deploy containerized systems. Docker Swarm allows developers to easily scale their applications to meet the scaling needs of the business, without having to worry about the complexities of managing a more flexible, distributed system.

Another important feature of Docker Swarm is its support for service updates and continuous deployment cycles. With rolling updates, developers can update their systems containerized services, one service at a time, without having to take the entire system offline. This helps to minimize downtime and ensures that the system remains highly available to the users.

Docker Swarm also provides solutions for load balancing, network virtualization, etc… These features help to work with, organize and deploy containerized solutions, making it easier for developers to build and maintain larger, distributed systems.

Implementation of a Clustered Environment using Docker Swarm

Docker Swarm is a tool for managing and deploying containerized solution across multiple hosts. In this chapter, we will explore how to set up a clustered environment using Docker Swarm and answer some common questions about the process.

Pre-Requisites

Before we get started, we need to ensure that we have the following pre-requisites in place:

Creating a Swarm Cluster

To create a Swarm, run the following command on the Docker host that you want to be the Swarm manager:

docker swarm init

This command initializes a new Swarm and makes the current Docker host the manager. The --advertise-addr flag is used to specify the IP address that the manager should advertise to other nodes in the Swarm.

Docker Swarm Manager Nodes

A Docker manager node is a node in the Swarm cluster responsible for managing the cluster state and coordinating tasks. The manager node is responsible for distributing tasks to worker nodes and maintaining the state of the cluster.
In a Docker Swarm cluster, it is recommended to have an odd number of manager nodes to prevent a split-brain scenario where the cluster gets partitioned into two independent sub-clusters. It is recommended to have at least three managers to ensure the reliability and availability of the cluster.

To add more manager nodes to the cluster, you first need to generate a join token on the existing manager node:

docker swarm join-token manager

This command will generate a join token that you can use to add new manager nodes to the cluster. You can then copy and paste the token on the new manager node to join the existing Swarm cluster as a manager:

docker swarm join --token <TOKEN> <MANAGER-IP>:2377

Docker Swarm Worker Nodes

A Docker Swarm worker node is a node in the Swarm cluster responsible for running tasks that have been assigned by the manager node. Worker nodes do not participate in cluster management and do not have access to the Swarm API.

To add a worker node to the Docker Swarm cluster previously initiated, you first need to generate a join token on an existing manager node:

docker swarm join-token worker

This command will generate a join token that you can use to add new worker nodes to the cluster. You can then copy and paste the token on the new worker node to join the existing Swarm cluster as a worker:

docker swarm join --token <TOKEN> <MANAGER-IP>:2377

Creating a Docker Swarm Service

Docker Swarm allows developers to easily create and manage a containerized system that are distributed across multiple hosts, making it an ideal tool for building and deploying microservices. In this chapter, we’ll explore Docker Swarm services, and how to run and replicate a service. Once the Swarm is set up and nodes have been added, we can start creating services. A service is a definition of a task that should be run on the Swarm, and Docker Swarm will ensure that the service is running on the appropriate nodes.

To create a service, run something like the following command:

docker service create --name server --replicas 3 -p 80:80 nginx

In this example, we’re creating a service named “server” with 3 replicas, using the nginx container image, and mapping port 80 of the container to port 80 of the host.

Once the service is created, we can use the docker service ls command to view the status of all services in the swarm, including the webserver we just created.

docker service ls

ID                  NAME                MODE                REPLICAS            IMAGE                        PORTS
o9vn0rsx8ob8        server              replicated          3/3                 nginx:latest                 *:80->80/tcp

Replicating a Service

One of the key benefits of Docker Swarm is its support for service replication, which allows us to easily scale our applications to meet the needs of the business. To replicate a service, we can use the docker service scale command:

docker service scale server=5

In this example, we’re scaling the “server” service to five replicas. Docker Swarm will automatically create and distribute these replicas across the available nodes in the swarm, ensuring that our application is highly available and resilient to node failures.

Using Replicas in a Clustered Solution

Replicas play a key role in a clustered solution, as they provide both scalability and fault tolerance. By distributing replicas across multiple nodes in the swarm, we can ensure that our application can continue to function even if one or more nodes fail. And by scaling the number of replicas up or down, we can easily adjust our system’s capacity to meet the demands of the business.

For example, if we’re running a web server that experiences a sudden spike in traffic, we can quickly scale up the number of replicas to handle the increased load. And if one or more nodes fail, Docker Swarm will automatically reschedule the affected replicas onto other nodes, ensuring that our solution remains available to users.

Docker Swarm services is a tool for building and deploying containerized applications in a clustered environment. By using replicas to distribute our services across multiple nodes in the swarm, we can ensure that our system is scalable and highly available.

Scaling in a Clustered Environment using Docker Swarm

Scaling refers to the ability of a software system to handle increasing workloads or growing amounts of data.

Horizontal Scaling

Adding manager and worker nodes as needed to scale your system, and ensure high availability, is called horizontal scaling.

Horizontal scaling is generally preferred over vertical scaling because it allows for an easier and more cost-effective scaling of systems. With horizontal scaling, adding more resources involves adding more machines or nodes to a system, which can be done quickly and without downtime.

Clustered environments benefit from horizontal scaling by allowing the distribution of workload across multiple nodes or machines in the cluster. By adding more nodes horizontally to the cluster, the workload can be distributed more evenly, which results in better resource utilization and higher availability.

Furthermore, horizontal scaling enables easier fault tolerance and resiliency in the system. If one node fails or experiences a disruption, the workload can be automatically shifted to other nodes in the cluster, ensuring that the system continues to serve according to high availibility policies.

Vertical Scaling

While horizontal scaling is generally preferred in clustered environments, it is also worth mentioning that it’s possible to utelize vertical scaling in a cluster. Vertical scaling involves adding more resources to existing machines or nodes, typically by upgrading the hardware, such as adding more memory or processing power.

In a clustered environment, vertical scaling can be useful when a particular node or machine within the cluster is experiencing performance issues or resource constraints. Upgrading the hardware of that node or machine can help solve these issues without having to add additional machines to the cluster.

It’s important to note that vertical scaling in a cluster can be more complex than in a non-clustered environment. For example, upgrading the hardware of one node or machine may require to align the hardware of all nodes or machines in the cluster to maintain uniformity and ensure a balanced resource allocation.

When Docker Swarm gives you Trouble

Check the Logs

Inspect the logs of the Docker daemon, Swarm manager nodes or specific Docker containers for clues about the issue.
You can use the following commands to view logs:

Docker daemon:

sudo journalctl -u docker.service

Swarm node:

docker node logs <node_id>

Swarm service:

docker service logs <service_id>

Docker container:

docker logs <container_id>

Reclaiming a Docker Swarm Cluster with the --force-new-cluster Flag

When working with Docker Swarm, it’s possible to encounter an error message that says there is no leader for the swarm. This error message typically appears when there are not enough managers online in the cluster. In this case, you can reclaim the cluster by reinitializing it with the --force-new-cluster flag.

To reclaim a Docker Swarm cluster using the --force-new-cluster flag, you’ll need to run the following command:

docker swarm init --force-new-cluster

This command will reinitialize the swarm cluster, effectively removing the old cluster and creating a new one. This will allow you to reclaim control over the cluster and continue managing your Docker services.

In some cases, you may also need to specify the IP address to advertise with the --advertise-addr flag. This is particularly relevant if there are multiple IP addresses on the host machine, as it tells the joining nodes how to connect to the leader. In such cases, you can run the following command:

docker swarm init --force-new-cluster --advertise-addr <ip_address>

Here, you should replace <ip_address> with the actual IP address of the machine you want to use as the leader. Once you have run this command, you should be able to reclaim control over your Docker Swarm cluster and continue working with your Docker services.

Trace issues with Services and Replicas in Docker Swarm

To check if the replicas of a service are up or not, you can use the docker service ls command. This command will list all of the services running on the Swarm, along with the number of replicas that are currently running.

For example, if you have a service named “server” with three replicas, you can use the following command to check the status of the service:

docker service ls

This will output a list of all services running on the swarm, along with information about each service. The output will look something like this:

ID                  NAME                MODE                REPLICAS            IMAGE                        PORTS
o9vn0rsx8ob8        server              replicated          3/3                 nginx:latest                 *:80->80/tcp

In this example, the “server” service has three replicas and all of them are up and running, as indicated by the “3/3” under the “REPLICAS” column. If any of the replicas are down or not running, the number will be lower than the desired number of replicas, example:

ID                  NAME                MODE                REPLICAS            IMAGE                        PORTS
o9vn0rsx8ob8        server              replicated          2/3                 nginx:latest                 *:80->80/tcp

If you notice that the replicas are not running as expected, it’s helpful to use the docker service ps command to check the status of individual replicas within a service. The output of this command provides information about the status of each replica, including which node it’s running on, the desired and current state, and any error messages associated with the replica.

ID                  NAME                IMAGE               NODE            DESIRED STATE       CURRENT STATE                ERROR               PORTS
uwwrptqqwmvj        server.1            nginx:latest        worker-05       Running             Running about an hour ago                        
i9b8pv6em9rl         \_ server.1        nginx:latest        worker-01       Shutdown            Shutdown about an hour ago                       
hwx8vo9yagls         \_ server.1        nginx:latest        worker-03       Shutdown            Shutdown about an hour ago                       
eg89rm0htcaw         \_ server.1        nginx:latest        worker-05       Shutdown            Complete 4 hours ago                             
tdl29w1g12y5        server.2            nginx:latest        worker-05       Running             Running about an hour ago                        
9hrf14vx0m8d         \_ server.2        nginx:latest        worker-05       Shutdown            Shutdown about an hour ago                       
8hmdu51vuykg         \_ server.2        nginx:latest        worker-01       Shutdown            Shutdown about an hour ago                       
t5qp12m23yot         \_ server.2        nginx:latest        worker-03       Shutdown            Complete 2 hours ago                             
pbq6ew1wv3pn        server.3            nginx:latest        worker-03       Running             Running about an hour ago                        
qagmo6uqrrdc         \_ server.3        nginx:latest        worker-05       Shutdown            Shutdown about an hour ago                       
7865qajaj2jq         \_ server.3        nginx:latest        worker-03       Shutdown            Shutdown about an hour ago                       
cms2tpm2lrvl         \_ server.3        nginx:latest        worker-01       Shutdown            Complete 4 hours ago

Finally, you can use the docker service update command to update the service and restart the replicas. For example, if you want to update the “server” service and restart the replicas, you can use the following command:

docker service update --force server

server
overall progress: 3 out of 3 tasks 
1/3: running   [==================================================>] 
2/3: running   [==================================================>] 
3/3: running   [==================================================>] 
verify: Service converged

This will force an update of the “server” service and restart any replicas that are not running. After the update is complete, you can use the docker service ls command again to verify that the replicas are up and running.

Troubleshooting Docker Host Issues without Cluster Downtime

A node’s availability can be set to either “active” or “drain”. When a node is set to “drain”, it is marked as unavailable for new tasks and existing tasks are rescheduled onto other available nodes.

To set a node’s availability to “drain”, you can use the following command:

docker node update --availability drain <node-id>

This command would mark the node as unavailable for new tasks and reschedule any existing tasks onto other available nodes. This can be useful in situations where a node is suspected to be problematic or corrupt.

It’s important to note that setting a node to “drain” does not remove it from the swarm. The node will still be part of the swarm and can be reactivated by setting its availability back to “active” using the same command with the --availability active option.

Label Docker Swarm Nodes

Sometimes it’s usefull to set labels on nodes, for instance to align with deployment constraints of which host the replicated service should run on.

docker node update --label-add foo=bar worker-01

This command adds a label foo with the value bar to the node worker-01 in a Docker Swarm.

Monitoring of Docker Swarm

The docker stats command is a useful tool for monitoring the resource usage of containers running on a Docker worker node. When you run this command, you’ll see a list of statistics related to each container, including CPU and memory usage, network I/O, and block I/O.

CONTAINER ID   NAME      CPU %     MEM USAGE / LIMIT     MEM %     NET I/O        BLOCK I/O    PIDS
a6f5d6cf0c7e   server    0.01%     6.645MiB / 1.952GiB   0.33%     8.92kB / 0B    12MB / 0B    2

By using the docker stats command, you can easily identify containers that are utilizing more resources than average. This can be an indicator of containers that need to be optimized or containers that have a memory leak. Keeping an eye on these resource usage metrics can help you proactively manage your Docker environment and prevent issues before they arise.

Inspect in Docker Swarm

When you need to display detailed information about a Docker object, such as a container, image, network, or volume, then you need to inspect the object. The information returned can include things like the object’s configuration, networking information, and status.

For example, if you run the command docker inspect <container-id>, you’ll get a detailed JSON output of the container’s configuration, such as its network settings, environment variables, and the volumes mounted inside.

docker service inspect <service-id> provides detailed information about a service in a Docker Swarm. You can use this command to view a service’s configuration, replicas, and placement constraints.

docker network inspect <network-id> can be used to inspect the configuration of a Docker network. This includes information about the network’s IP address range, subnet, gateway, and DNS settings.

These commands are useful for troubleshooting and debugging Docker objects in general. By inspecting the objects you can easily read their configuration and state past configuring the object.

Orchestration with Docker Swarm supported by the Superhero Tool Chain

Superhero Stack Services for Supporting Your Docker Swarm Cluster

The Superhero Stack provides a range of services designed to enhance and support your Docker Swarm cluster. These services include:

Key Features and Benefits of the Tools in the Stack of the Superhero Tool Chain

The Superhero Tool Chain provides tools that can complement your Docker Swarm cluster. Here are some of the key features and benefits of these tools:

Custom and Automated Deployment Flow

The Superhero Deployment Service offers an automated deploy functionality that allows you to define “deploy templates” written in JavaScript. These templates can be used to pipeline the deploy process into a custom CI/CD flow that meets your business needs. This enables you to deploy your applications faster and with more consistency.

Centralized Security Design

The Superhero Reverse Proxy Service is responsible for routing traffic into the Docker Swarm cluster. All traffic enters through this service, which means that it is the perfect place to handle SSL encryption. This centralized approach to security ensures that your entire cluster is protected, and that all traffic is encrypted in transit.

Inherited Round-Robin Load Balancing

The Superhero Reverse Proxy Service also provides load balancing functionality by distributing traffic evenly across replicas of the same service. This is made possible through Docker Swarm’s built-in round-robin strategy, which ensures that traffic is balanced and that no single service instance is overloaded.

Simple Approach to Event Sourcing

The Superhero Eventsource Service offers a simple approach to event sourcing, which can lead to improved traceability in the development and production cycle. This service provides a persistence layer that facades a series of composed Redis interactions designed to offer event source functionality. With this service, you can easily track events and troubleshoot issues in your applications.

Implementation of a Clustered Environment Supported by the Superhero Tool Chain

The Superhero Stack Services can be cloned and updated with new configurations to later be built and deployed to support your stack.

Superhero Deployment Service

To use the Superhero Deployment Service, you simply need to push any changes to the private GitHub remote, and the service will automatically deploy the changes.

Superhero Reverse Proxy Service

After installation, the Superhero Reverse Proxy Service will automatically handle the routing and SSL encryption for your cluster.

Superhero Eventsource Service

After installation, the Superhero Eventsource Service will provide enhanced traceability in the development and production cycle. You can view logs for transparency, but there is nothing that you can directly interact with in the service.

Designing Software for a Clustered Environment

Challenges of Designing for a Clustered Environment

Designing for a clustered environment can present challenges that require consideration and planning. Here are some of the main challenges that organizations may face when implementing a clustered environment:

Scalability

One of the biggest concerns when designing for a clustered environment is ensuring that the system can scale to meet the demands of the workload. This involves determining how many nodes are needed in the cluster, how much processing power and memory each node should have, and how to balance the workload across the cluster.

High availability

Another challenge is ensuring that the system remains available and responsive even in the event of failures or outages. This requires implementing redundancy and failover mechanisms to ensure that services are automatically restarted on healthy nodes in the cluster.

Data consistency

In a clustered environment, data consistency can be a challenge due to the distributed nature of the system. Organizations must carefully consider how data will be synchronized and maintained across the cluster to ensure that all nodes have access to the same information.

How the Superhero Tool Chain Can Help Overcome Those Challenges

Designing for a clustered environment can pose challenges related to scalability, high availability, and data consistency. However, the Superhero Tool Chain offers specific solutions that can address some of these challenges.

Scalability

The Superhero Tool Chain provides a solutions through its reversed proxy and event source services. These services scale automatically with the stack when new nodes are added or when services are scaled to new amounts of replicas.

High Availability

The Superhero Tool Chain ensures high availability through Docker Swarm’s failover mechanism. If a service fails, Docker Swarm restarts the failing container. The Superhero Reverse Proxy Service utilizes the Docker Swarm DNS, which allows DNS records to be updated on failover, preventing “Bad Gateway” exceptions that can occur during failovers.

Data Consistency

The Superhero Tool Chain and the Superhero Stack do not persist data in any solution, ensuring data consistency across the service cluster by not persisting data in the service cluster…

Best Practices

To ensure a secure and robust clustered environment, a few points recommended to follow:

Last Gasp

Key takeaways

Recommendations to building microservice systems with the Superhero Tool Chain