Building a robust application (Introduction I)

The beauty of an application infrastructure-wise is its robustness. The word robust in this context means the application’s ability to handle challenges proactively based on measures that have been put in place. In this article, I will introduce various measures to consider when building a robust application. This is a series, and this is just the introduction. In this introduction, I will outline the solutions, but explain each of the outlined items further in other series.

When building an application, taking proactive measures for infrastructure and ensuring the application is robust and resilient are crucial. Below are measures you can take to ensure you have a robust application.

N/b: This series will revolve around AWS and Azure.

High Availability (HA)

Designing infrastructure for high availability and minimal downtime is a critical consideration. I will outline various measures to take when doing this either with AWS, Azure, or On-prem.

AWS

1. Availability Zones (AZs): Deploy resources across multiple availability zones within an AWS region. This provides redundancy and resiliency.
2. Elastic Load Balancing: Use AWS Elastic Load Balancers (ELB) to distribute traffic across multiple instances in different availability zones.
3. Auto Scaling: Set up Auto Scaling groups to automatically adjust the number of instances based on traffic and resource usage.
4. Multi-Region Deployment: Consider a multi-region architecture for higher availability, especially for critical applications.
5. Database Replication: Use RDS (Relational Database Service) for database replication across availability zones or regions.
6. Content Delivery: Use AWS CloudFront for content delivery to reduce latency and increase availability.
7. Pod and node autoscaling: If you are using Kubernetes for your application, you will need to factor in horizontal pod autoscaler (HPA) and cluster autoscaler.
8. Route 53 DNS Failover: Utilize Amazon Route 53 to configure DNS failover, directing traffic to a healthy instance in case of failure.

Azure

1. Availability Sets: Use Azure Availability Sets to distribute VM instances across fault domains and update domains.
2. Load Balancers: Employ Azure Load Balancers to distribute traffic across multiple VMs for redundancy.
3. Azure Autoscale: Implement Azure Autoscale to automatically adjust the number of VMs based on performance metrics.
4. Geo-Replication: Use Azure Geo-Replication for services like Azure SQL Database to replicate data across regions.
5. Azure Traffic Manager: Configure Azure Traffic Manager for DNS-based load balancing and failover.
6. Pod and node autoscaling: If you are using Kubernetes for your application, you will need to factor in horizontal pod autoscaler (HPA) and cluster autoscaler.
7. ExpressRoute: Set up Azure ExpressRoute for dedicated and redundant network connections to Azure.

Data Encryption

Encrypting sensitive data, both in transit and at rest, is crucial for protecting the security and privacy of your data. I will be highlighting below their usage in AWS and Azure.

In transit (Using HTTPS)

1. TLS/SSL Certificates: Obtain and configure SSL/TLS certificates for your web servers or load balancers. You can use services like AWS Certificate Manager (ACM) or Azure Key Vault to manage certificates.
2. Secure Protocols and Ciphers: Ensure that only secure and up-to-date encryption protocols and ciphers are used to establish HTTPS connections. Disable weak protocols and ciphers.
3. Secure Configuration: Configure your web servers or load balancers to enforce the use of HTTPS. Redirect HTTP traffic to HTTPS to ensure data remains encrypted.
4. Certificate Management: Regularly renew and monitor SSL/TLS certificates to prevent certificate expiration issues.

At Rest (Using Encryption Mechanisms)

AWS

1. S3 Data Encryption: Enable server-side encryption for Amazon S3 buckets. You can use SSE-S3, SSE-KMS, or SSE-Customer-Provided Keys to encrypt data at rest.
2. EBS Encryption: When using Amazon Elastic Block Store (EBS) for EC2 instances, enable EBS encryption to encrypt data at rest.
3. RDS Encryption: Encrypt data stored in Amazon RDS instances by enabling the encryption option during database creation or enabling encryption on existing databases.
4. Key Management Services: Use AWS Key Management Service (KMS) to manage and secure encryption keys. KMS allows you to create, rotate, and control access to encryption keys.
5. Elastic File System (EFS): Encrypt data stored in Amazon EFS by enabling encryption at the file system level.

Azure

1. Azure Disk Encryption: Enable Azure Disk Encryption to encrypt data on Azure virtual machine disks at rest.
2. Azure Storage Service Encryption: Use Azure Storage Service Encryption to encrypt data stored in Azure Blob Storage, Azure Files, and Azure Queue Storage.
3. SQL Database Encryption: Encrypt data in Azure SQL Database using Transparent Data Encryption (TDE).
4. Azure Key Vault: Use Azure Key Vault to manage and safeguard encryption keys. You can store keys and secrets securely in Key Vault.
5. Azure Data Lake Storage: Encrypt data in Azure Data Lake Storage by enabling encryption at rest.
6. Managed Disk Encryption: Use Azure’s managed disk encryption for securing data stored in managed disks.

Performance optimization

Monitoring application performance, load testing, and implementing caching mechanisms are critical for optimizing application performance in both AWS and Azure. Here are key considerations for each aspect:

Monitoring Application Performance

AWS

1. Amazon CloudWatch: Use CloudWatch to collect and analyze performance data, set alarms, and visualize metrics for AWS resources.
2. CloudWatch Logs: Collect logs from your applications and systems and set up log monitoring in CloudWatch for real-time analysis.
3. AWS X-Ray: Employ AWS X-Ray for tracing and profiling of requests to identify bottlenecks and performance issues in microservices.
4. Custom Metrics: Create custom CloudWatch metrics to track specific application performance indicators relevant to your application.

Azure

1. Azure Monitor: Use Azure Monitor to collect and analyze performance data, set up alerts, and visualize metrics for Azure resources.
2. Application Insights: Implement Application Insights to gain insights into application performance, detect issues, and troubleshoot.
3. Azure Log Analytics: Collect and analyze logs from applications and infrastructure using Log Analytics to identify performance issues.

Load testing

AWS

1. AWS Elastic Beanstalk: Deploy applications using Elastic Beanstalk, which provides built-in tools for load testing and scaling resources.
2. AWS Load Testing Tools: AWS offers tools like AWS Amplify for mobile app load testing and AWS Device Farm for mobile device testing.

Azure

1. Azure Load Testing: Use Azure Load Testing to simulate realistic load on your application and measure performance.
2. Azure DevTest Labs: Azure DevTest Labs allows you to create isolated testing environments for load testing.
3. Visual Studio Team Services (VSTS): Utilize VSTS to create and manage load tests, including cloud-based load testing in Azure.

Caching mechanism: We implement caching mechanisms to reduce load on databases and servers. See it’s usage below.

AWS

1. Amazon ElastiCache: Use ElastiCache to deploy and manage in-memory caching with Redis or Memcached to reduce database load and improve response times.
2. Amazon CloudFront: Set up CloudFront to cache content at edge locations for faster content delivery, especially for static assets.

Azure

1. Azure Cache for Redis: Use Azure Cache for Redis to implement in-memory caching for improved application performance.
2. Azure Content Delivery Network (CDN): Leverage Azure CDN to cache and serve content from edge servers, reducing latency and improving response times.
3. Redis Cache: Azure also offers a managed Redis Cache service for caching and accelerating data access.

Security measures

Securing applications and infrastructure by updating and patching components, as well as implementing a Web Application Firewall (WAF), is crucial for protecting against security vulnerabilities in both AWS and Azure. Here’s how you can approach these security measures in both cloud platforms:

Updating and Patching Components

AWS

1. Amazon EC2 Instances: Regularly update the operating system and software on your EC2 instances using package managers or automated patch management tools.
2. Amazon RDS and Aurora: AWS manages the underlying infrastructure, including security updates for RDS and Aurora databases, but you should keep your database engines up to date.
3. Elastic Beanstalk and Lambda: AWS updates the underlying runtime environments, but you should regularly update your application code to address vulnerabilities.
4. Amazon Linux: AWS provides Amazon Linux, which includes security updates. Ensure that instances running Amazon Linux are regularly updated.
5. AWS Inspector: Use AWS Inspector to assess the security and compliance of your EC2 instances and applications. It helps identify vulnerabilities that need attention.

Azure

1. Azure Virtual Machines: Regularly apply OS updates and patches to your virtual machines in Azure. Azure provides update management services for this purpose.
2. Azure SQL Database: Azure manages security updates for its managed database services, but you need to ensure your application code is secure and up-to-date.
3. Azure App Service: Keep your application code updated, as Azure App Service manages the underlying runtime environment.
4. Azure Kubernetes Service (AKS): Update your AKS cluster and applications running within the cluster to patch vulnerabilities.
5. Azure Security Center: Utilize Azure Security Center to assess the security posture of your resources, identify vulnerabilities, and apply recommended security updates.

Implementing a Web Application Firewall (WAF)

Amazon Web Services (AWS)

1. AWS WAF: Set up AWS WAF to protect your web applications from common web exploits. Configure WAF rules and conditions to block malicious traffic.
2. AWS CloudFront Integration: If you’re using Amazon CloudFront for content delivery, integrate AWS WAF with CloudFront to protect against DDoS attacks and other security threats.
3. Logging and Monitoring: Enable logging for AWS WAF to monitor traffic and identify suspicious activity. Use Amazon CloudWatch and AWS CloudTrail for analysis.

Azure

1. Azure Application Gateway WAF: Implement Azure Application Gateway with Web Application Firewall (WAF) to protect your web applications from common web threats.
2. Azure Front Door: Azure Front Door also offers WAF capabilities. Configure WAF policies and rules to filter and protect your web traffic.
3. Security Center: Use Azure Security Center to monitor and manage your security policies, including WAF, and gain insights into security threats.
4. Logging and Alerting: Configure logs and alerts for the WAF to be notified of suspicious activity and to respond to potential threats in real-time.

Protecting containerized applications

Protecting containerized applications in both AWS and Azure requires a comprehensive approach to security. Here are some key measures to enhance the security of containerized applications in both cloud platforms:

Amazon Web Services (AWS)

1. Amazon EKS (Elastic Kubernetes Service) Security: Use Amazon EKS to manage your Kubernetes clusters securely. EKS offers features like control plane encryption and VPC integration. Implement fine-grained access control by configuring RBAC (Role-Based Access Control) to limit what resources can be accessed by users and pods.
2. Security Groups and Network Policies: Use AWS security groups and Kubernetes network policies to control network traffic between pods and clusters.
3. Container Registry Security: Use Amazon Elastic Container Registry (ECR) to store and manage your container images securely. Enable encryption and access controls on your ECR repositories.
4. AWS Security Tools: Leverage AWS security services like AWS Identity and Access Management (IAM), AWS Key Management Service (KMS), AWS CloudTrail, and AWS Config for monitoring and governance.
   Vulnerability Scanning:

5. Use container security tools to scan container images for vulnerabilities before deployment. Tools like AWS ECR Image Scanning or third-party solutions tools like Trivy or sonarcube can help.

Azure

1. Azure Kubernetes Service (AKS) Security: Use AKS to deploy and manage your Kubernetes clusters securely. AKS integrates with Azure AD for user authentication. Implement role-based access control (RBAC) to control access to AKS resources.
2. Network Security Groups: Define Network Security Groups (NSGs) and configure Azure Virtual Networks to control network traffic to and from AKS clusters.
3. Azure Container Registry Security: Use Azure Container Registry (ACR) for storing and managing container images securely.
   Implement role-based access control (RBAC) for ACR and enable content trust.
4. Azure Security Center: Enable Azure Security Center for container security monitoring, threat detection, and compliance assessments.
5. Azure Policy: Use Azure Policy to define and enforce governance for container deployments.
6. Vulnerability Scanning: Implement vulnerability scanning of container images using tools like Azure Container Registry vulnerability scanning or third-party solutions tools like Trivy and sonarcube.

Conclusion

Remember, employing these measures is up to how your system is designed, you may not need to employ all as they are generic, but applying most of them will boast the robustness of your infrastructure.