Tag: DevOps

Browse all articles, tutorials, and guides about DevOps

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Terraform
2025-06-20|5 min read

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.

Kubernetes
2025-06-01|5 min read

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
2025-06-01|5 min read

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.

Docker
2025-05-18|7 min read

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.

Docker
2025-05-04|7 min read

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.

Kubernetes
2025-04-25|8 min read

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.

Kubernetes
2025-04-15|8 min read

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.

Kubernetes
2025-04-05|6 min read

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.

Kubernetes
2025-03-30|6 min read

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.

Terraform
2025-03-21|6 min read

Best practices when using Terraform?

Discover essential best practices for using Terraform to manage your infrastructure effectively and securely.

Terraform
2025-03-20|5 min read

How to create an SSH key in Terraform?

Learn how to generate and manage SSH keys in Terraform for secure access to your infrastructure.

DevOps
2025-03-10|5 min read

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.

Terraform
2025-02-20|4 min read

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.

Terraform
2025-02-15|5 min read

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.

Terraform
2025-02-05|5 min read

Conditional Attributes in Terraform

Learn how to use conditional expressions to dynamically set resource attributes in Terraform.

Terraform
2025-01-30|6 min read

Managing Different Environments in Terraform

Learn how to manage different environments in Terraform using workspaces, variable files, and directory structures.

Terraform
2025-01-20|5 min read

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.

Terraform
2025-01-20|6 min read

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.

Terraform
2025-01-10|5 min read

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.

AWS
2025-01-02|5 min read

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.

Docker
2024-12-20|7 min read

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.

Docker
2024-12-15|8 min read

Delete All Local Docker Images Safely

Learn how to reclaim disk space by removing Docker images, containers, and volumes without breaking your development workflow.

Kubernetes
2024-12-13|8 min read

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.

Terraform
2024-12-09|5 min read

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.

Docker
2024-12-05|7 min read

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.

Kubernetes
2024-12-01|7 min read

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.

Docker
2024-12-01|7 min read

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.

Terraform
2024-12-01|7 min read

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.

Docker
2024-11-30|6 min read

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.

Docker
2024-11-25|6 min read

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.

Docker
2024-11-20|8 min read

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
2024-11-20|8 min read

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.

Terraform
2024-11-20|5 min read

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.

CI/CD
2024-11-18|7 min read

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.

Docker
2024-11-15|6 min read

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.

Terraform
2024-11-15|4 min read

How do you do simple string concatenation in Terraform?

Learn how to perform string concatenation in Terraform using interpolation and the join function.

Terraform
2024-11-15|6 min read

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.

Docker
2024-11-15|7 min read

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
2024-11-10|6 min read

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.

Docker
2024-11-10|7 min read

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.

Kubernetes
2024-11-10|5 min read

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.

Docker
2024-11-08|6 min read

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.

Terraform
2024-11-05|6 min read

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
2024-11-05|6 min read

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.

Terraform
2024-11-02|5 min read

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.

Docker
2024-11-01|5 min read

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.

Terraform
2024-11-01|5 min read

Variables Within Variables in Terraform

Learn how to use variables within variables in Terraform to create dynamic and reusable configurations.

AWS
2024-10-30|7 min read

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.

Terraform
2024-10-29|5 min read

How to Display Sensitive Data Output Variables in Terraform

Learn how to handle and display sensitive data output variables in Terraform safely and effectively.

Terraform
2024-10-23|7 min read

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
2024-10-22|7 min read

Docker Image vs Container: Key Differences

Learn the fundamental difference between Docker images and containers through practical examples and real-world scenarios.

Terraform
2024-10-20|6 min read

Terraform + DynamoDB: All Attributes Must Be Indexed

Learn how to handle the 'all attributes must be indexed' requirement in DynamoDB when using Terraform.

DevOps
2024-10-18|7 min read

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.

Kubernetes
2024-10-12|6 min read

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.

Docker
2024-10-11|5 min read

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.

Docker
2024-10-05|7 min read

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.

Kubernetes
2024-09-28|6 min read

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
2024-09-18|12 min read

Docker Security Best Practices

Secure your Docker environment from development to production with practical techniques for image hardening, runtime protection, and vulnerability management.

Python
2024-09-15|6 min read

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
2024-09-10|6 min read

Docker - Ubuntu - bash: ping: command not found [closed]

Resolve the 'ping: command not found' error in Ubuntu-based Docker containers by installing missing packages.

Networking
2024-09-01|7 min read

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.

Kubernetes
2024-09-01|5 min read

kubectl logs - Continuously

Learn how to use kubectl to stream logs continuously from Kubernetes Pods for real-time monitoring.

FinOps
2024-08-22|12 min read

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
2024-08-20|5 min read

Kubernetes: How to Make Deployment to Update Image

Learn how to update the container image in a Kubernetes Deployment using kubectl commands.

Terraform
2024-08-15|5 min read

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.

Kubernetes
2024-08-13|6 min read

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.

Networking
2024-08-12|5 min read

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.

Terraform
2024-08-10|5 min read

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.

Kubernetes
2024-08-10|6 min read

Service Located in Another Namespace

Learn how to access and interact with Kubernetes Services located in different namespaces.

Docker
2024-08-01|8 min read

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.

Kubernetes
2024-08-01|5 min read

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.

Kubernetes
2024-08-01|6 min read

Listing All Resources in a Namespace

Learn how to list all resources in a Kubernetes namespace using kubectl commands.

Networking
2024-07-30|8 min read

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.

Terraform
2024-07-26|5 min read

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.

Terraform
2024-07-24|5 min read

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.

Docker
2024-07-15|8 min read

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.

Kubernetes
2024-07-10|7 min read

Checking Kubernetes Pod CPU and Memory Utilization

Learn how to monitor CPU and memory usage of Kubernetes Pods using kubectl and metrics-server.

Kubernetes
2024-07-10|6 min read

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.

Kubernetes
2024-07-01|6 min read

At Least One Invalid Signature Was Encountered

Understand the causes of invalid signatures in Kubernetes and learn how to troubleshoot and resolve them.

Kubernetes
2024-07-01|7 min read

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.

Terraform
2024-06-21|5 min read

Is there an AND/OR Conditional Operator in Terraform?

Learn how to use AND/OR conditional operators in Terraform to create dynamic configurations.

Kubernetes
2024-06-20|6 min read

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.

Terraform
2024-06-19|5 min read

Refactoring modules: Error: Provider configuration not present

Learn how to resolve the 'Provider configuration not present' error when refactoring Terraform modules.

Terraform
2024-06-17|4 min read

How can I remove a resource from Terraform state?

Learn how to safely remove a resource from Terraform state without affecting the actual infrastructure.

Terraform
2024-06-16|5 min read

How are data sources used in Terraform?

Understand how to use data sources in Terraform to fetch information about existing resources.

Kubernetes
2024-06-15|7 min read

How Does kubectl port-forward Create a Connection?

Understand how kubectl port-forward works to create connections between your local machine and Kubernetes Pods.

Terraform
2024-06-15|5 min read

Upgrade Terraform to Specific Version

Learn how to upgrade Terraform to a specific version on your system, ensuring compatibility with your infrastructure.

Terraform
2024-06-11|5 min read

Initial setup of Terraform backend using Terraform

Learn how to configure a Terraform backend for secure and efficient state management.

Docker
2024-06-10|8 min read

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.

Kubernetes
2024-06-10|7 min read

Real-World Kubernetes Deployments

Lessons learned from deploying Kubernetes in production environments.

Kubernetes
2024-06-01|5 min read

Get YAML for Deployed Kubernetes Services

Learn how to retrieve the YAML configuration for deployed Kubernetes Services using kubectl commands.

Docker
2024-05-22|6 min read

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.

Networking
2024-05-21|5 min read

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.

Kubernetes
2024-05-20|7 min read

How Can I Debug "ImagePullBackOff"?

Learn how to troubleshoot and resolve the ImagePullBackOff error in Kubernetes Pods.

Kubernetes
2024-05-20|5 min read

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.

Terraform
2024-05-15|5 min read

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.

Kubernetes
2024-05-10|6 min read

Restart Pods When ConfigMap Updates in Kubernetes

Learn how to restart Kubernetes Pods automatically when a ConfigMap is updated.

Terraform
2024-05-05|6 min read

How to Migrate Terraform State Between Projects

Learn how to safely migrate Terraform state between projects using the `terraform state` command.

Docker
2024-05-01|8 min read

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.

Kubernetes
2024-04-25|7 min read

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
2024-04-22|6 min read

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.

Terraform
2024-04-21|6 min read

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.

Docker
2024-04-18|8 min read

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.

Docker
2024-04-05|7 min read

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
2024-03-29|7 min read

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.

Terraform
2024-03-21|6 min read

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
2024-03-12|5 min read

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.

Kubernetes
2024-03-12|7 min read

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.

Docker
2024-03-03|7 min read

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.

Terraform
2024-02-21|4 min read

Concatenate a String with a Variable in Terraform

Learn how to concatenate strings with variables in Terraform to create dynamic configurations.

Docker
2024-02-19|6 min read

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.

Kubernetes
2024-02-18|5 min read

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.

Docker
2024-02-14|8 min read

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.

Docker
2024-01-28|4 min read

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
2024-01-23|5 min read

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.

Kubernetes
2024-01-22|8 min read

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.

Kubernetes
2024-01-10|6 min read

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
2024-01-05|8 min read

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
2024-01-02|7 min read

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.