Tag: DevOps
Browse all articles, tutorials, and guides about DevOps
Guides
Introduction to Docker
Learn how to use Docker to build, ship, and run applications efficiently through containerization
Introduction to Kubernetes
Learn how to orchestrate containerized applications at scale with Kubernetes
Introduction to CI/CD with GitHub Actions
Learn to automate your development workflow with GitHub Actions, from basic builds to sophisticated deployment pipelines.
A Practical Guide to FinOps for DevOps Engineers
Learn how to implement FinOps practices in your DevOps workflows to optimize cloud costs while maintaining performance and reliability.
Networking Fundamentals for Developers
A comprehensive guide to computer networking concepts, from basic protocols to advanced cloud networking and automation.
Introduction to Ansible
Learn how to automate server configuration and deployment tasks with Ansible, from basic concepts to production-ready practices.
Posts
A Day in the Life of a DevOps Engineer
Follow a DevOps engineer through a typical day - from morning deployments to midnight hotfixes. Real challenges, real solutions, and real impact on business operations.
How to Use the AWS account_id Variable in Terraform
Learn how to dynamically retrieve and use the AWS account_id variable in Terraform for your configurations.
Command to Delete All Pods in All Kubernetes Namespaces
Learn how to delete all Pods across all namespaces in Kubernetes using a single command. Understand the implications and best practices for this operation.
Terraform Conditionals: Handling Non-Existent Variables
Learn how to use Terraform conditionals to handle cases where a variable does not exist or is not defined.
How Docker Differs from a Virtual Machine (And Why It Matters)
Containers and virtual machines both isolate environments, but they work in very different ways. This guide explains the key differences and when to use each.
How to Copy Docker Images Between Hosts Without a Repository
Learn how to transfer Docker images directly between machines when a container registry is unavailable or impractical.
How Can I Trigger a Kubernetes Scheduled Job Manually?
Learn how to manually trigger a Kubernetes Scheduled Job to run on demand. Understand the steps, commands, and best practices for this operation.
Namespace "Stuck" as Terminating: How Do I Remove It?
Learn how to resolve the issue of a Kubernetes namespace stuck in the Terminating state. Understand the causes and steps to fix it.
How to Switch Namespace in Kubernetes
Learn how to switch between namespaces in Kubernetes using kubectl commands and configuration files. Understand the importance of namespaces and practical examples.
How Do I Force Kubernetes to Re-Pull an Image?
Learn how to force Kubernetes to re-pull container images to ensure your Pods use the latest version. Understand the steps and implications of this operation.
Best practices when using Terraform?
Discover essential best practices for using Terraform to manage your infrastructure effectively and securely.
How to create an SSH key in Terraform?
Learn how to generate and manage SSH keys in Terraform for secure access to your infrastructure.
Where Does the Convention of Using /healthz for Application Health Checks Come From?
Discover the origins of the /healthz endpoint convention for application health checks and why it has become a standard in modern software development.
Should I commit .tfstate files to Git?
Understand why committing .tfstate files to Git is not recommended and explore best practices for managing Terraform state.
Specifying an API Gateway Endpoint with a Variable in Terraform
Learn how to dynamically specify an API Gateway endpoint with a variable in Terraform for flexible configurations.
Conditional Attributes in Terraform
Learn how to use conditional expressions to dynamically set resource attributes in Terraform.
Managing Different Environments in Terraform
Learn how to manage different environments in Terraform using workspaces, variable files, and directory structures.
terraform.tfvars vs variables.tf: What is the Difference?
Understand the difference between terraform.tfvars and variables.tf in Terraform and how to use them effectively.
Use Terraform to set up a Lambda function triggered by a scheduled event source
Learn how to use Terraform to create an AWS Lambda function triggered by a scheduled event source, such as a cron job.
How to Load Input Data from a File in Terraform
Learn how to load input data from a file in Terraform using the `file` function and external data sources.
Correct way to attach AWS managed policies to a role?
Learn how to correctly attach AWS managed policies to an IAM role using the AWS Management Console, CLI, or Terraform.
How to Upgrade a Docker Container After Its Image Changed
Learn how to upgrade a Docker container to use a new version of its image without downtime.
Delete All Local Docker Images Safely
Learn how to reclaim disk space by removing Docker images, containers, and volumes without breaking your development workflow.
kubectl apply vs kubectl create: Understanding the Key Differences
Learn the differences between kubectl apply and kubectl create commands, when to use each, and how they handle resource management in Kubernetes deployments.
How to Ignore Change of an Attribute in Terraform Blocks
Learn how to use the `lifecycle` block with the `ignore_changes` argument to ignore changes to specific attributes in Terraform.
How to Rebuild a Docker Container in docker-compose.yml?
Learn how to rebuild Docker containers defined in a docker-compose.yml file, including tips for managing changes and dependencies.
What is the Difference Between a Pod and a Deployment?
Understanding the difference between Pods and Deployments in Kubernetes is crucial for managing containerized applications effectively. Learn how they work and when to use each.
What is the Difference Between "Expose" and "Publish" in Docker?
Understanding the difference between 'expose' and 'publish' in Docker is crucial for managing container networking effectively. Learn how these concepts work and when to use them.
How to Split a Terraform File (main.tf) into Several Files (No Modules)
Organizing Terraform configurations by splitting a single main.tf file into multiple files can improve readability and maintainability. Learn how to do this without using modules.
How to Enter a Docker Container Already Running with a New TTY
Learn how to attach to a running Docker container with a new TTY session for debugging or interaction.
Difference Between RUN and CMD in a Dockerfile
Understand the key differences between RUN and CMD in a Dockerfile, and learn when to use each for building and running Docker containers.
How to Access Host Port from Docker Container
Learn how to access a host machine's port from a Docker container using network configurations and best practices.
Docker Complains About "No Space Left on Device": How to Clean Up?
Running out of space while using Docker can disrupt your workflow. Learn how to identify and clean up unused Docker resources to free up space.
How to Execute Terraform Actions Without the Interactive Prompt
Learn how to automate Terraform workflows by bypassing the interactive prompt for commands like apply and destroy.
The GitHub Actions Workflow That Eliminated Our DevOps Bottleneck
How we reduced deployment time from 2 hours to 8 minutes using smart GitHub Actions patterns and parallel execution strategies.
How to Fix Docker: Permission Denied
Getting a 'permission denied' error when using Docker can be frustrating. Here's how to fix it depending on the OS, Docker command, and user setup.
How do you do simple string concatenation in Terraform?
Learn how to perform string concatenation in Terraform using interpolation and the join function.
How to for_each through a list(objects) in Terraform
Learn how to use the for_each construct in Terraform to iterate through lists of objects and dynamically create resources.
How to Push a Docker Image to a Private Repository
Learn how to push a Docker image to a private repository, including authentication and best practices for secure image management.
AWS ASG Launch Templates vs Launch Configurations
Understand the key differences between AWS Auto Scaling Group Launch Templates and Launch Configurations to make informed decisions for your infrastructure.
How Can I Expose More Than One Port with Docker?
Learn how to expose multiple ports in Docker to enable complex containerized applications with multiple services.
How to List All Pods and Their Nodes in Kubernetes
Learn how to list all pods in your Kubernetes cluster along with the nodes they're running on, using kubectl and command-line tools for clear, actionable output.
How to Remove Old Docker Containers
Over time, stopped Docker containers pile up and take up space. Learn how to list, filter, and clean up unused containers safely and efficiently.
How to Attach Multiple IAM Policies to IAM Roles Using Terraform
Learn how to attach multiple IAM policies to a single IAM role in Terraform to manage permissions effectively.
Docker: Name is Already in Use by Container
Encountering the 'name is already in use by container' error in Docker? Learn why it happens and how to resolve it effectively.
Fixing the "Invalid Legacy Provider Address" Error in Terraform
Learn how to resolve the 'Invalid legacy provider address' error in Terraform by upgrading your provider configurations.
How Do I Pass Environment Variables to Docker Containers?
Environment variables are a clean way to configure your Docker containers without hardcoding values. This guide shows different methods and when to use each.
Variables Within Variables in Terraform
Learn how to use variables within variables in Terraform to create dynamic and reusable configurations.
How to Nuke All AWS Resources in an AWS Account
Learn how to safely and efficiently delete all resources in an AWS account using tools like AWS CLI and Terraform.
How to Display Sensitive Data Output Variables in Terraform
Learn how to handle and display sensitive data output variables in Terraform safely and effectively.
Determining Minimum AWS Permissions for Terraform Configurations
Learn how to identify the minimum AWS permissions required for your Terraform configurations to enhance security and compliance.
Docker Image vs Container: Key Differences
Learn the fundamental difference between Docker images and containers through practical examples and real-world scenarios.
Terraform + DynamoDB: All Attributes Must Be Indexed
Learn how to handle the 'all attributes must be indexed' requirement in DynamoDB when using Terraform.
Should I Use Vagrant or Docker for Creating an Isolated Environment?
Choosing between Vagrant and Docker depends on your workflow and what kind of isolation you need. This guide walks through real-world use cases to help you decide.
How to Update a Kubernetes Secret Generated from a File
Learn how to update an existing Kubernetes secret when its data comes from a file, with practical kubectl commands and tips for safe secret management.
How to Get a Docker Container's IP Address from the Host
Learn how to find a Docker container's internal IP address from your host machine using simple Docker commands. This is useful for debugging, testing services, or container communication.
In a Dockerfile, How to Update the PATH Environment Variable?
Learn how to modify the PATH environment variable in a Dockerfile to include custom directories for executables.
How to Clean Up ReplicaSets When Updating Kubernetes Deployments
Learn how and when to clean up old ReplicaSets after updating Kubernetes Deployments, why they accumulate, and how to manage rollout history for a tidy cluster.
Docker Security Best Practices
Secure your Docker environment from development to production with practical techniques for image hardening, runtime protection, and vulnerability management.
Finding Local IP Addresses Using Python's stdlib
Learn how to find the local IP address of your machine using only Python's standard library. No third-party packages required.
Docker - Ubuntu - bash: ping: command not found [closed]
Resolve the 'ping: command not found' error in Ubuntu-based Docker containers by installing missing packages.
How to Get Your Local IP Address
Learn multiple methods to find your local IP address using command line tools, programming languages, and system utilities across different operating systems.
kubectl logs - Continuously
Learn how to use kubectl to stream logs continuously from Kubernetes Pods for real-time monitoring.
What Is FinOps? A Beginner's Guide to Cloud Cost Management
Discover how FinOps transforms chaotic cloud spending into strategic financial operations, bringing teams together to optimize costs while maintaining innovation speed.
Kubernetes: How to Make Deployment to Update Image
Learn how to update the container image in a Kubernetes Deployment using kubectl commands.
Fixing "A Reference to Resource Type Must Be Followed by At Least One Attribute Access" in Terraform
Learn how to resolve the error 'A reference to resource type must be followed by at least one attribute access' in Terraform.
How to Sign In to the Kubernetes Dashboard
Learn how to securely access and sign in to the Kubernetes Dashboard, including token generation, best practices, and troubleshooting common login issues.
How to Find Which Process Is Listening on a Port in Windows
Need to know which application is using a specific TCP or UDP port on Windows? Here's how to check using netstat, tasklist, PowerShell, and Resource Monitor.
How to Create a Folder in an AWS S3 Bucket Using Terraform
Learn how to create a folder in an AWS S3 bucket using Terraform by leveraging the `aws_s3_object` resource.
Service Located in Another Namespace
Learn how to access and interact with Kubernetes Services located in different namespaces.
What is the Runtime Performance Cost of a Docker Container?
Understand the runtime performance impact of Docker containers compared to virtual machines and bare-metal systems.
How to Cleanly List All Containers in a Kubernetes Pod
Learn several ways to list all containers in a Kubernetes pod using kubectl and JSONPath, with practical examples for real-world troubleshooting and automation.
Listing All Resources in a Namespace
Learn how to list all resources in a Kubernetes namespace using kubectl commands.
How to Artificially Create a Connection Timeout Error
Learn practical methods to simulate connection timeouts for testing error handling, resilience patterns, and timeout configurations in your applications.
Using a Git Branch as a Source for Terraform Modules
Learn how to use a specific Git branch as the source for Terraform modules to manage versioning and development workflows.
Getting an Environment Variable in Terraform Configuration
Learn how to retrieve and use environment variables in Terraform configurations using the `env` function and input variables.
How to Assign a Port Mapping to an Existing Docker Container
Learn how to assign a port mapping to an already running Docker container using practical workarounds and best practices.
Checking Kubernetes Pod CPU and Memory Utilization
Learn how to monitor CPU and memory usage of Kubernetes Pods using kubectl and metrics-server.
How Can I Keep a Container Running on Kubernetes?
Learn how to ensure your container stays running on Kubernetes by using proper configurations and best practices.
At Least One Invalid Signature Was Encountered
Understand the causes of invalid signatures in Kubernetes and learn how to troubleshoot and resolve them.
How to Delete All Resources from Kubernetes at One Time
Learn how to delete all resources in a Kubernetes namespace or cluster using kubectl commands.
Docker Can't Connect to Docker Daemon
Learn how to troubleshoot and resolve the Docker can't connect to Docker daemon error effectively.
Is there an AND/OR Conditional Operator in Terraform?
Learn how to use AND/OR conditional operators in Terraform to create dynamic configurations.
Why Does a Kubernetes Pod Get Recreated When Deleted?
Learn why Kubernetes automatically recreates Pods when they are deleted, and understand the mechanisms behind this behavior.
Refactoring modules: Error: Provider configuration not present
Learn how to resolve the 'Provider configuration not present' error when refactoring Terraform modules.
How can I remove a resource from Terraform state?
Learn how to safely remove a resource from Terraform state without affecting the actual infrastructure.
How are data sources used in Terraform?
Understand how to use data sources in Terraform to fetch information about existing resources.
How Does kubectl port-forward Create a Connection?
Understand how kubectl port-forward works to create connections between your local machine and Kubernetes Pods.
Upgrade Terraform to Specific Version
Learn how to upgrade Terraform to a specific version on your system, ensuring compatibility with your infrastructure.
Initial setup of Terraform backend using Terraform
Learn how to configure a Terraform backend for secure and efficient state management.
How to Run a Docker Image as a Container
Learn how to start a container from a Docker image, pass environment variables, map ports, and manage container lifecycle.
Real-World Kubernetes Deployments
Lessons learned from deploying Kubernetes in production environments.
Get YAML for Deployed Kubernetes Services
Learn how to retrieve the YAML configuration for deployed Kubernetes Services using kubectl commands.
How to Mount a Host Directory in a Docker Container
Learn how to mount a local directory into a Docker container for development, data sharing, or configuration. This guide covers syntax, permissions, and real-world use cases.
What Is the Difference Between a Port and a Socket?
Ports and sockets are often mentioned together in networking, but they serve different roles. This guide breaks down what they are and how they work together.
How Can I Debug "ImagePullBackOff"?
Learn how to troubleshoot and resolve the ImagePullBackOff error in Kubernetes Pods.
How to Copy Files from Kubernetes Pods to Local System
Learn how to use kubectl commands to copy files from Kubernetes Pods to your local system.
I would like to run Terraform only for a specific resource
Learn how to target specific resources in Terraform to save time and avoid unnecessary changes.
Restart Pods When ConfigMap Updates in Kubernetes
Learn how to restart Kubernetes Pods automatically when a ConfigMap is updated.
How to Migrate Terraform State Between Projects
Learn how to safely migrate Terraform state between projects using the `terraform state` command.
Docker Push Error: denied: requested access to the resource is denied
Troubleshoot and resolve the common Docker push error about denied access to a resource. Learn about authentication, repository naming, and permissions.
Difference Between targetPort and port in Kubernetes Service Definition
Understand the distinction between targetPort and port in Kubernetes Service definitions, and learn how they impact your application's networking.
Terraform - Delete All Resources Except One
Learn how to delete all resources managed by Terraform except for a specific resource by using targeted commands and state manipulation.
How to Write an if, else, elsif Conditional Statement in Terraform
Learn how to use if, else, and elsif conditional statements in Terraform to create dynamic configurations.
How to Edit a File After You Shell to a Docker Container
Learn how to edit files inside a running Docker container using shell access, text editors, and best practices for persistent changes.
Cannot Connect to the Docker Daemon at unix:/var/run/docker.sock. Is the Docker Daemon Running?
Troubleshoot the common Docker error about not being able to connect to the Docker daemon. Learn why it happens and how to fix it on Linux and macOS.
Terraform Failing with Invalid for_each Argument / The Given "for_each" Argument Value is Unsuitable
Learn how to troubleshoot and fix the "Invalid for_each argument" error in Terraform.
Can Terraform Be Used to Provision On-Premises Servers?
Learn how Terraform can be used to provision on-premises servers by integrating with tools like VMware vSphere, Ansible, and bare-metal providers.
Docker: How to Change Repository Name or Rename an Image
Learn how to rename a Docker image or change its repository name using simple Docker CLI commands. This guide covers real-world scenarios and best practices.
How to Set Multiple Commands in One YAML File with Kubernetes
Learn how to define and run multiple commands in a Kubernetes Pod using a single YAML manifest. This guide covers best practices and real-world examples for multi-step container initialization.
How to Remove a Docker Image
Learn how to safely remove Docker images, clean up unused layers, and avoid common pitfalls when managing local images.
Concatenate a String with a Variable in Terraform
Learn how to concatenate strings with variables in Terraform to create dynamic configurations.
How to See Docker Image Contents
Explore the contents of a Docker image using practical commands. Learn how to inspect layers, browse files, and debug images locally.
How to Decode a Kubernetes Secret
Kubernetes secrets store sensitive data in base64-encoded form. Learn how to safely decode and inspect these secrets using kubectl and command-line tools.
How to Include Files Outside of Docker's Build Context
Learn why Docker restricts file access during builds, and how to work around this limitation to include files outside the build context.
How to List Containers in Docker
Learn how to list running and stopped Docker containers, filter by status, and get useful details for troubleshooting and management.
Terraform Statefile is Locked: How to Unlock It
Learn how to unlock a locked Terraform statefile using the `force-unlock` command and best practices to avoid future locks.
How to Manage Multiple Environments in Kubernetes (Staging, QA, Production)
Learn practical strategies for managing multiple Kubernetes environments like staging, QA, and production. This guide covers namespace organization, configuration management, and deployment workflows.
How to Restart a Container Within a Kubernetes Pod
Learn practical ways to restart a container inside a Kubernetes pod, including when and why you might need to do this, and the best approaches for different scenarios.
Kubernetes Pods Keep Crashing with CrashLoopBackOff but No Logs Found
Troubleshoot Kubernetes pods stuck in CrashLoopBackOff with no logs. Learn why this happens and how to diagnose and resolve the issue.
Kubernetes Deployments vs StatefulSets
Understand the differences between Kubernetes Deployments and StatefulSets, when to use each, and how they impact your application's behavior and scaling.