Introduction
Understanding Resilience
Resilience is a system's ability to adapt to adverse conditions. The
conditions could be
Resilience is about a system's capability to handle failures.
Architecture Design
Identify the core components of the system such web apps, APIs, databases
and storage
Design the overall system keeping in mind factors like high availability,
scalability and disaster recovery
Use services that provide built-in redundancy and failover mechanisms, such
as Load Balancing and Failover Groups
Compute and Scaling
For web apps and APIs, use Azure App Service or Azure Functions that provide
automatic scaling and high availability
For background tasks or event-driven workloads, consider using Azure
Functions or Azure Logic Apps
For databases, use Azure SQL Database or Azure Cosmos DB which can
automatically scale resources based on demand
Implement autoscaling rules and policies to automatically scale resources up
or down based on metrics and performance thresholds
Data Storage and Resilience
Choose appropriate Azure storage service such as Azure Blob Storage, Azure
Files or Azure Data Lake Storage
Implement geo-redundancy and backup strategies to ensure data resilience and
disaster recovery
Consider using Azure Cosmos DB when you need a highly scalable NOSQL
database
Networking and Load Balancing
Use Azure Virtual Network to create a secure and isolated network
environment for the resources
Utilize Azure Load Balancer or Azure Application Gateway to distribute
traffic across multiple instances of your application
Implement traffic routing and failover mechanisms to ensure high
availability and resilience
Monitoring and Diagnostics
Set up Azure Monitor to collect and analyze logs, metrics and performance
data from the Azure resources
Configure Azure Application Insights to gain deeper insights into the
performance and health of the web apps and APIs
Deployment and CI/CD
Adopt a DevOps approach by implementing a continuous integration and
continuous deployment (CI/CD) pipeline using Azure DevOps or GitHub Actions
Automate the deployment process to ensure consistent and reliable
deployments
Use Azure Resource Manager (ARM) templates or Bicep files to define and
manage your infrastructure as code
Security and Compliance
Implement Azure Active Directory (Azure AD) for user authentication and
access management
Use Azure Key Vault to securely store and manage the application's sensitive
data such as secrets, certificates and encryption keys
Ensure the system complies with relevant industry standards and regulations
by using Azure's security and compliance features
Disaster Recovery and Business Continuity
Establish a comprehensive disaster reovery plan including backup strategies,
geo-replication and failover mechanisms
Use Azure Site Recovery to replicate the virtual machines to a secondary
region and enable fast failover in cae of a disaster
Test the disaster recovery plan regularly to ensure it works as expected
Remember, building a reliable and scalable system in Azure is an ongoing
process that requires continuous monitoring, optimization and improvement.
It is essential to regularly review the system's performance, costs and
security to ensure it continues to meet your requirements
Achieving Stability
Design Considerations
It is paramount to design a system to be resilient. The system should be
designed to detect and respond to failures.
One of the strategies was to use the best hardwares and softwares to build
the system. The best hardwares ensure its failures are rare or minimum.
Using software to build resilience is an economical and flexible option.
Software/scripts can be written to create logs of various activities/states
to identify possible points of failure.
Conclusion
Citation
Firesmith, D., 2019: System Resilience: What Exactly is it?. Carnegie Mellon
University, Software Engineering Institute's Insights (blog), Accessed
January 8, 2025,
https://insights.sei.cmu.edu/blog/system-resilience-what-exactly-is-it/.