# ercan.cloud > Cloud, Kubernetes, AWS, infrastructure, and platform engineering writing by Ercan Ermis. Senior-engineer voice for a 201-level audience. ## Sections ### AWS - [Agent Auth on AWS: OIDC In, Access Keys Out](https://ercan.cloud/agent-auth-on-aws-oidc-in-access-keys-out/): Agents on AWS should never hold long-lived keys. How OIDC federation, IRSA, Roles Anywhere, and AgentCore Identity turn signed proof into temporary credentials. - [Agent Toolkit for AWS: The Docs Have a New Reader](https://ercan.cloud/agent-toolkit-for-aws-the-docs-have-a-new-reader/): AWS shipped the Agent Toolkit: an MCP server, curated skills, and IAM guardrails for coding agents. The primary reader of AWS docs is not human anymore. - [FinOps: Budget Alerts with Terraform Before Your Next $2.5B AWS Bill](https://ercan.cloud/finops-budget-alerts-with-terraform/): The July 17 Cost Explorer bug filled every feed with billion-dollar AWS bills. Ten lines of Terraform give you the budget alerts that caught it first. - [Local DynamoDB Grew Up: A Hands-On Look at ExtendDB](https://ercan.cloud/local-dynamodb-grew-up-a-hands-on-look-at-extenddb/) - [IaC-First: Why I am Never Touch the AWS Console in Production](https://ercan.cloud/iac-first-why-we-never-touch-the-aws-console-in-production/) - [AWS S3 New Feature: Re-encryption without Movement](https://ercan.cloud/aws-s3-new-feature-re-encryption-without-movement/) - [AWS Monthly (Nov '25) The Stateful Serverless Revolution](https://ercan.cloud/aws-monthly-nov-25-the-stateful-serverless-revolution/): November and re:Invent 2025 brought us the "holy grail" of serverless: AWS Lambda Durable Functions. This feature introduces... - [When the Cloud Sneezes, the World Catches a Cold - Lessons from the us-east-1 Meltdown](https://ercan.cloud/when-the-cloud-sneezes-the-world-catches-a-cold-lessons-from-the-us-east-1-meltdown/) - [AWS Monthly (Sep '25): Vega OS & eBPF Observability](https://ercan.cloud/aws-monthly-sep-25-vega-os-ebpf-observability/): In a surprise move, AWS released Vega OS in September. Vega is a specialized, Linux-based OS optimized for the edge and high-performance UI... - [AWS Monthly (Aug '25): Big Data, Zero Effort](https://ercan.cloud/aws-monthly-aug-25-big-data-zero-effort/): August was all about "Data Gravity." Amazon Aurora storage limits jumped to 256 TiB, which effectively ends the "sharding" conversation for... - [AWS Monthly (July '25): Kubernetes at the Edge of Sanity](https://ercan.cloud/aws-monthly-july-25-kubernetes-at-the-edge-of-sanity/): July was a landmark month for the EKS (Elastic Kubernetes Service) crowd. AWS announced that EKS now supports 100,000-node clusters. - [AWS Monthly (May '25): The Death of the War Room](https://ercan.cloud/aws-monthly-may-25-the-death-of-the-war-room/): May brought CloudWatch Investigations, which have fundamentally changed someone's on-call rotation. Instead of manual log correlation, ... - [Automating AWS CloudWatch Log Group Tagging with Python and Boto3](https://ercan.cloud/automating-aws-cloudwatch-log-group-tagging-with-python-and-boto3/) - [Automating AWS ECR Tagging with Python and Boto3](https://ercan.cloud/automating-aws-ecr-tagging-with-python-and-boto3/) - [Automating ECR Image Cleanup with Bash](https://ercan.cloud/automating-ecr-image-cleanup-with-bash/) - [Update ECR Repositories with Bash Script](https://ercan.cloud/update-ecr-repositories-with-bash-script/) - [AWS Monthly (April '25): Cooling the AI Heat](https://ercan.cloud/aws-monthly-april-25-cooling-the-ai-heat/): In April, AWS gave us a peek behind the curtain of their data center engineering. To handle the thermal output of the latest AI clusters, ... - [AWS Monthly (Mar '25): The Proximity Power Play](https://ercan.cloud/aws-monthly-mar-25-the-proximity-power-play/): Technically, this brings "Single-Digit Millisecond Latency" to almost every major tech hub. If you are building AR/VR backends, indust... - [Streamline Your AWS ECR Management with This Powerful Bash Script](https://ercan.cloud/streamline-your-aws-ecr-management-with-this-powerful-bash-script/) - [AWS Monthly (Jan '25): Shattering the 6MB Ceiling](https://ercan.cloud/aws-monthly-jan-25-shattering-the-6mb-ceiling/) - [Setting up DKIM for Google Workspace (Gmail) using Terraform and AWS Route 53](https://ercan.cloud/setting-up-dkim-for-google-workspace-gmail-using-terraform-and-aws-route-53/): DKIM (DomainKeys Identified Mail) is a critical email authentication technique that helps prevent email spoofing. By using DKIM, you ... - [Automate AWS Site-to-Site VPN Monitoring](https://ercan.cloud/automate-aws-site-to-site-vpn-monitoring/): That’s exactly why I created the AWS Site-to-Site VPN Monitoring Script, a tool designed to automate the monitoring of VPN connections ... - [Monitoring EC2 Disk Space with a Simple Bash Script and Slack Alerts](https://ercan.cloud/monitoring-ec2-disk-space-with-a-simple-bash-script-and-slack-alerts/): In the cloud infrastructure landscape, monitoring the health and resources of EC2 instances is essential. One common challenge for system... - [Accessing AWS Services in Private Subnets Without 0.0.0.0/0](https://ercan.cloud/accessing-aws-services-in-private-subnets-without-0-0-0-0-0/): When working with AWS (Amazon Web Services), securing your infrastructure is paramount. One of the most common security practices is to ... - [Understanding AWS Regions, Availability Zones, and VPCs: A Comprehensive Guide](https://ercan.cloud/understanding-aws-regions-availability-zones-and-vpcs/): In today's cloud computing landscape, Amazon Web Services (AWS) has established itself as a leader, offering a wide range of services to ... - [AWS Network Load Balancers with Header Modification Techniques](https://ercan.cloud/aws-network-load-balancers-with-header-modification-techniques/): AWS Network Load Balancers (NLBs) are a powerful tool for distributing incoming application traffic across multiple targets... - [AWS VPC IP Versions: IPv4 vs. IPv6](https://ercan.cloud/aws-vpc-ip-versions-ipv4-vs-ipv6/): So, buckle up as we unravel the mysteries of IPv4 and IPv6 within AWS VPC, serving you a platter of insights, examples, and detailed ... - [AWS S3 CORS Settings: A Deep Dive](https://ercan.cloud/aws-s3-cors-settings-a-deep-dive/): Whether you're a seasoned AWS veteran or just starting, mastering CORS settings in S3 can greatly enhance your web applications' functiona... - [Importance of Regions and Availability Zones on AWS](https://ercan.cloud/importance-of-regions-and-availability-zones-on-aws/): We're diving into a pivotal aspect of architecting robust, resilient, and efficient applications on Amazon Web Services (AWS): understand... - [AWS VPC Design: Integrating Subnets, AZs, and Dual-Stack IP](https://ercan.cloud/aws-vpc-design-integrating-subnets-azs-and-dual-stack-ip/): Virtual Private Cloud (VPC) in AWS, meticulously weaving together subnets, availability zones (AZs), and the dual-stack configuration for... - [Understanding CAA DNS Records: What, Why, and How?](https://ercan.cloud/understanding-caa-dns-records-what-why-and-how/): CAA, or Certificate Authority Authorization, is a type of DNS record that allows domain owners to specify which Certificate ... - [Mastering AWS VPC: An Introduction to Virtual Private Cloud Routing](https://ercan.cloud/mastering-aws-vpc-an-introduction-to-virtual-private-cloud-routing/): The world of cloud computing has never been more accessible or diverse. As organizations migrate to the cloud, AWS ... - [Understanding the New AWS Public IPv4 Address Charge and Public IP Insights](https://ercan.cloud/understanding-the-new-aws-public-ipv4-address-charge-and-public-ip-insights/) - [The AWS Well-Architected Framework: A Key to Cloud Success](https://ercan.cloud/the-aws-well-architected-framework-a-key-to-cloud-success/): The cloud has revolutionized the way businesses operate, and Amazon Web Services (AWS) has consistently led the charge in cloud ... - [Secure Your Media Files by Removing Metadata with AWS Lambda](https://ercan.cloud/secure-your-media-files-by-removing-metadata-with-aws-lambda/): Enhance privacy and security across various industries by stripping EXIF and other metadata from uploaded images and videos - [List your S3 bucket objects easily with S3 Directory Listing](https://ercan.cloud/list-your-s3-bucket-objects-easily-with-s3-directory-listing/): Introducing S3-Directory-Listing, a simple and easy-to-use JS script and HTML combo that will turn your S3 bucket directory listing into ... - [What is Carrier Gateway on AWS?](https://ercan.cloud/what-is-carrier-gateway-on-aws/): Amazon Web Services (AWS) offers many services to provide a seamless and secure cloud computing experience to its users. One of these ... - [Creating SSH Keys for Secure Access to AWS EC2 Instances with Terraform](https://ercan.cloud/creating-ssh-keys-for-secure-access-to-aws-ec2-instances-with-terraform/): When working with cloud infrastructure, security is of utmost importance. One critical aspect of security is controlling access to cloud ... - [What is an Egress only internet gateways in AWS?](https://ercan.cloud/what-is-an-egress-only-internet-gateways-in-aws/): Within a VPC, an Egress-Only Internet Gateway is an essential component that enables outbound traffic from the VPC to the Internet. - [What is an Internet Gateway in AWS?](https://ercan.cloud/what-is-an-internet-gateway-in-aws/) - [What are Route Tables on AWS VPC?](https://ercan.cloud/what-are-route-tables-on-aws-vpc/) - [What is Subnet on AWS VPC?](https://ercan.cloud/what-is-subnet-on-aws-vpc/): Subnets in AWS VPC are used to divide a VPC into multiple logical networks. This allows users to isolate resources and control access to ... - [What is AWS VPC?](https://ercan.cloud/what-is-aws-vpc/): Learn about Amazon Web Services (AWS) Virtual Private Cloud (VPC), a service that allows users to create and manage their own virtual pri... - [Scaling PHP Applications on AWS](https://ercan.cloud/scaling-php-applications-on-aws/): You can understand the running highly available, performant, and secure PHP applications on AWS with easy 14 steps... - [Create an S3 Bucket and Set a Policy via CLI](https://ercan.cloud/create-an-s3-bucket-and-set-a-policy-via-cli/): I really like to use CLI commands and it's my daily routine. Today, I'll tell to you "How do you create an S3 Bucket on AWS" and "Put an ... - [Issue a Let's Encrypt SSL with the AWS Route53](https://ercan.cloud/issue-a-lets-encrypt-ssl-with-the-aws-route53/): In this article, I want to tell you how you can issue a Let's Encrypt SSL with the AWS Route53 service. Let's start to learn. - [Automate Let's Encrypt SSL on AWS Application Load Balancer](https://ercan.cloud/automate-lets-encrypt-ssl-on-aws-application-load-balancer/): In this article, you can automate all of Let's Encrypt issuing operations for AWS Application Load Balancer and learn how you can manage the.. - [Deploy a website to S3 and CloudFront with Bitbucket Pipelines](https://ercan.cloud/deploy-a-website-to-s3-and-cloudfront-with-bitbucket-pipelines/): In this article, you will learn how you can deploy your static website to the S3 Bucket and Cache Invalidation automatically... - [Protect your AWS Account with specified IPs](https://ercan.cloud/protect-your-aws-account-with-specified-ips/): You will learn, how you can protect your AWS account and the resources in the cloud with IAM Policy. Security is the first th... - [Differences between AWS CLI v1 and v2](https://ercan.cloud/differences-between-aws-cli-v1-and-v2/) - [I'm officially AWS Community Builder!](https://ercan.cloud/im-officially-aws-community-builder/): This morning, I've got an e-mail from @JasonDunn about the AWS Community Builder program. I don't remember when I applied to this program but - [Deploy HA nginx to AWS ECS with Geolocation Routing via Terraform](https://ercan.cloud/deploy-ha-nginx-to-aws-ecs-with-geolocation-routing-via-terraform/): You can deploy the nginx docker image in two different regions in AWS. If you need, you can add more region support by yout self... - [Deploy nginx docker to AWS ECS with Terraform Automation](https://ercan.cloud/deploy-nginx-docker-to-aws-ecs-with-terraform-automation/): You can understand how you can deploy nginx docker to AWS ECS with terraform easily. The terraform will handle everything what you need. - [Connect your AWS to GCP with Terraform via IPSec Site-to-Site VPN](https://ercan.cloud/connect-your-aws-to-gcp-with-terraform-via-ipsec-site-to-site-vpn/): You can deploy the VPN infrastructure easily with this article. Terraform is a automation tool you can do everyting in the cloud era. - [How to secure your Amazon Web Services account](https://ercan.cloud/how-to-secure-your-amazon-web-services-account/): Learn how to secure your Amazon Web Services account. Root level account has got full access to all resources running in the cloud enviro... - [Set two different Target Groups on AWS Load Balancer with Terraform](https://ercan.cloud/set-two-different-target-groups-on-aws-load-balancer-with-terraform/): You will learn how you can use more than one target group behind Elastic Load Balancer in aws services with Terraform. - [Create a New Grant User on AWS RDS (MariaDB)](https://ercan.cloud/create-a-new-grant-user-on-aws-rds-mariadb/): You will learn, how to create a grant user for your RDS. It's little bit complicated process but just follow the article and know. - [Amazon S3 CORS Settings with CloudFront on Amazon Web Services](https://ercan.cloud/amazon-s3-cors-settings-with-cloudfront-on-amazon-web-services/): Learn how to set for your aws S3 Bucket CORS settings on CloudFront in Amazon Web Services. CORS settings is taking security for your bucket. - [Fix "Error: rpmdb open failed" on CentOS or Amazon Linux 2](https://ercan.cloud/fix-error-rpmdb-open-failed-on-centos-or-amazon-linux-2/): If you having rpmdb issues with your yum, you can easily follow the same steps and fix your package manager in a minute. ### Uncategorized - [How I Found a Hidden Cloudflare Bug on a Sunday mid-night (The joy of curl)](https://ercan.cloud/how-i-found-a-hidden-cloudflare-bug-on-a-sunday-mid-night/): It was supposed to be a quick weekend project. You know the kind: "I'll just spin up an egress VM, route some traffic through it, sip my ... - [I dropped my Google Pixel 9 XL Pro from 6th floor balcony to the street](https://ercan.cloud/i-dropped-my-google-pixel-9-xl-pro-from-6th-floor-balcony-to-the-street/): My phone slipped out of my hand and executed a textbook, no-hesitation, full-commitment dive from the 6th floor straight to the street. - [I Built TrumpDaily to Track Donald Trump Without the Noise](https://ercan.cloud/https-trumpdaily-site-i-built-a-news-aggregator-so-i-can-finally-keep-up/): Look, tracking Trump is exhausting. The man dominates headlines across BBC, Guardian, NPR, Al Jazeera, and even Babylon Bee. Checking 10+ ... - [When Spotify’s Share-to-Instagram Flow Turns Into a Free Billboard](https://ercan.cloud/when-spotifys-share-to-instagram-flow-turns-into-a-free-billboard/): I dug into how Spotify generates story assets and wrote up the possible attack vectors + where the metadata pipelines might be vulnerabi... - [Why Automated Tests Are Essential in Your CI/CD Pipeline and Development Flow](https://ercan.cloud/why-automated-tests-are-essential-in-your-ci-cd-pipeline-and-development-flow/) - [Optimizing Docker Images: Tips for Reducing Image Size and Build Time](https://ercan.cloud/optimizing-docker-images-tips-for-reducing-image-size-and-build-time/): Hey, fellow Docker enthusiast! If you're here, you probably love Docker as much as I do, spinning up containers, packaging applications ... - [Securing Docker Containers: Best Practices for Container Security](https://ercan.cloud/securing-docker-containers-best-practices-for-container-security/): When we talk about containerization, Docker is often the first tool that comes to mind. It's revolutionized how we develop, ship, and ... - [Mastering Dockerfile: Writing Efficient, Scalable Container Builds](https://ercan.cloud/mastering-dockerfile-writing-efficient-scalable-container-builds/): Docker has revolutionized the way we develop, package, and ship applications. At the heart of this container magic is the Dockerfile, the ... - [Migrating a Git Repository from GitLab to GitHub with GPG-Signed Commits](https://ercan.cloud/migrating-a-git-repository-from-gitlab-to-github-with-gpg-signed-commits/): In today's DevOps-driven world, version control systems like Git are the backbone of software development. GitLab and GitHub are two of ... - [How to call multiple terraform modules in a single terragrunt file](https://ercan.cloud/how-to-call-multiple-terraform-modules-in-a-single-terragrunt-file/): in Terragrunt, you can call multiple Terraform modules from a single Terragrunt configuration file by using the terraform block in combi... - [Leveraging Git Hooks for Enforcing Commit Message Standards: A Guide for Cross-Platform Development Teams](https://ercan.cloud/leveraging-git-hooks-for-enforcing-commit-message-standards-a-guide-for-cross-platform-development-teams/) - [Simplifying SSL with Let's Encrypt and CLI.ini: A DevOps Guide](https://ercan.cloud/simplifying-ssl-with-lets-encrypt-and-cli-ini-a-devops-guide/): In the vast expanse of the internet, security is not just a luxury; it's a necessity. For web developers and system administrators, ... - [TCP vs. UDP: Navigating the Protocols as Developers and DevOps](https://ercan.cloud/tcp-vs-udp-navigating-the-protocols-as-developers-and-devops/): Understanding TCP and UDPBefore we dive into the differences, let's briefly understand what TCP and UDP are ... - [7 Reasons to Consider Getting a Smartwatch](https://ercan.cloud/7-reasons-to-consider-getting-a-smartwatch/) - [Docker Multi-Stage Builds: An In-depth Guide](https://ercan.cloud/docker-multi-stage-builds-an-in-depth-guide/) - [Mastering Docker Run Command: A Comprehensive Guide](https://ercan.cloud/mastering-docker-run-command-a-comprehensive-guide/) - [Ctrl+C and Ctrl+V party with GitHub Clone Helper!](https://ercan.cloud/ctrlc-and-ctrlv-party-with-github-clone-helper/): When you copy the clone URL, you're actually copying the entire 'git clone' command. It's the Ctrl+C and Ctrl+V party you always wanted ... - [Telnet Movies - A Nostalgic Look at the Dawn of Internet Movie Streaming](https://ercan.cloud/telnet-movies-a-nostalgic-look-at-the-dawn-of-internet-movie-streaming/): Long before Netflix, Hulu, and Amazon Prime Video transformed the way we consume content, there was a fascinating, lesser-known method... - [Keeping Composer Packages Up-to-Date with Composer Guardian: Why It's Essential](https://ercan.cloud/keeping-composer-packages-up-to-date-with-composer-guardian-why-its-essential/) - [Prevent nginx from caching DNS for proxy](https://ercan.cloud/prevent-nginx-from-caching-dns-for-proxy/): If you are having problems with nginx proxy DNS caching, you can see the config for flush and/or clear DNS caching continuously... - [What do I have?](https://ercan.cloud/what-do-i-have/): Apple MacBookPro M1, Dell XPS13 4K, Juniper SRX-110, Xiaomi 4A Router, Dell Pivot Monitor, Logitech MX Keys, Logitech MX Master 3. - [How to Install Node Exporter on Linux Server](https://ercan.cloud/how-to-install-node-exporter-on-linux-server/): You can monitor your Linux Server easily with Node Exporter. Node Exporter installation it little bit different but just follow the article.. - [FortiClient Problem on M1 MacBookPro Problem Solution](https://ercan.cloud/forticlient-problem-on-m1-macbookpro-problem-solution/): I found a quick fix solution for FortiClient VPN client connectivity issue with Apple M1 MacBookPro. It's not a big deal... - [Google Cloud Platform Automation with Terraform Easily](https://ercan.cloud/google-cloud-platform-automation-with-terraform-easily/): You can deploy your load balancer, instance template, instance group and firewall rules easily with terraform. - [Install UGREEN USB Ethernet Adapter on macOS](https://ercan.cloud/install-ugreen-usb-ethernet-adapter-on-macos/): Today, I need to connect my Apple MacBookPro Silicon to the internet via the same USB adapter but macOS doesn't like this. - [Redirect 301 HTTPS on App Engine with nginx on Google Cloud Platform](https://ercan.cloud/redirect-301-https-on-app-engine-with-nginx-on-google-cloud-platform/): You can learn how to redirect http requests turn to https easily. AppEngine and nginx will work smoothly after this tutorial. - [Take your GitLab backup everyday if it works in Docker](https://ercan.cloud/take-your-gitlab-backup-everyday-if-it-works-in-docker/): Learn how to automate your Docker GitLab backup. You should make a backup for your repository security. Let's automate the process... - [Juniper SRX110H-VA VDSL2 Configuration Step by Step](https://ercan.cloud/juniper-srx110h-va-vdsl2-configuration-step-by-step/): Set a VDSL2 connection for Juniper SRX-110 easily. I've already created a main configration and you can use if you need. Just edit few lines.. - [Enable Logrotation for Docker Containers](https://ercan.cloud/enable-logrotation-for-docker-containers/): Docker on your system, the container running in the docker can generate a large number of logs while you are not aware of the background. - [Hello Blog!](https://ercan.cloud/hello-blog/): My blog address contains my first name and my last name. So, you know my name I guess : ) ### Linux - [Why Your SSH Is Yelling About Quantum Computers (And How to Fix It)](https://ercan.cloud/why-your-ssh-is-yelling-about-quantum-computers-and-how-to-fix-it/) - [The Power of Bash For Loops: Streamlining Your Scripting Tasks](https://ercan.cloud/the-power-of-bash-for-loops-streamlining-your-scripting-tasks/): In the world of scripting and automation, Bash stands out as a versatile and widely-used shell in Unix and Linux systems. Among its ... - [How to Enable SSH on Ubuntu: A Step-by-Step Guide](https://ercan.cloud/how-to-enable-ssh-on-ubuntu-a-step-by-step-guide/): Secure Shell (SSH) is an essential tool for system administrators, developers, and IT professionals. It provides a secure way to access ... - [Vim: Mastering the Essentials for Efficient Editing](https://ercan.cloud/vim-mastering-the-essentials-for-efficient-editing/): In the world of text editing, Vim stands out as a powerful, keyboard-centric editor that prioritizes efficiency and speed. Originating ... - [MySQL 8: Understanding and Fixing Error 1819](https://ercan.cloud/mysql-8-understanding-and-fixing-error-1819/): As a beginner in MySQL, you might encounter an error message that reads "ERROR 1819 (HY000): Your password does not satisfy the current ... - [Unveiling the Mystery: Decoding IP Address Retrieval in Linux](https://ercan.cloud/unveiling-the-mystery-decoding-ip-address-retrieval-in-linux/): Understanding how to retrieve an IP address in Linux can be a bit tricky, especially for beginners. The good news? It's not as complicated... - [CORS in Nginx: Configuration Guide for Enhanced Security](https://ercan.cloud/cors-in-nginx-configuration-guide-for-enhanced-security/): Cross-Origin Resource Sharing (CORS) is a crucial mechanism for enabling secure communication between web servers and browsers. - [SSL CA Problem on CentOS7 Docker and Solution](https://ercan.cloud/ssl-ca-problem-on-centos7-docker-and-solution/) - [Extend your ec2 Linux disk without reboot on Amazon Web Services](https://ercan.cloud/extend-your-ec2-linux-disk-without-reboot-on-amazon-web-services/): Just follow the steps and learn how to extend without reboot. Normally, It's realy hard to extend the Linux servers root disk. - [Find large files in CentOS, ubuntu and MacOS easily](https://ercan.cloud/find-large-files-in-centos-ubuntu-and-macos-easily/): Sometimes, it's really hard to find the big files path Linux. In this tutorial, you will learn how you can find it easily. - [Error: No space left on the device when starting/stopping services only](https://ercan.cloud/error-no-space-left-on-the-device-when-starting-stopping-services-only/): Learn how to fix "No space left on the device" error when starting and/or stopping services only on Amazon Linux 2 - [Download specific file extension via wget easily on terminal](https://ercan.cloud/download-specific-file-extension-via-wget-easily-on-terminal/): Sometimes, there may be files with more than one extension in a directory or folder. For example, .jpg, .png, .gif, .mp3, .mp4 etc. - [Find the exact size of certain files in Linux via terminal](https://ercan.cloud/find-the-exact-size-of-certain-files-in-linux-via-terminal/): You may be wondering about the size of these files or just want to see the size of the files with the corresponding extension for a ... - [Disable SELinux on CentOS 7 or CentOS 8](https://ercan.cloud/disable-selinux-on-centos-7-or-centos-8/): This tutorial shows you how you can disable SELinux on your CentOS server. The CentOS version should be CentOS 7 or CentOS 8. - [AWS Multi-party Approval for Organizations](https://ercan.cloud/aws-organizations-multi-party-approval/): Multi-party approval in AWS Organizations gates high-risk operations behind a quorum of human approvers. Here is how it works and the security it buys. - [No Phone, No Account: Google's QR Wall and GDPR](https://ercan.cloud/google-qr-phone-verification-gdpr/): Google now gates new account creation behind a phone-based QR verification. No smartphone, no account. Here is why that collides with GDPR data minimization. - [AWS Lambda MicroVMs: Serverless Gets a Stateful, Isolated Sandbox](https://ercan.cloud/aws-lambda-microvms-serverless-sandboxes/): AWS Lambda MicroVMs add VM-level isolation, snapshot-fast launch, and suspend-resume state to serverless, powered by Firecracker. What changes and where it fits. ### Security - [Checking Cloud with Cloud: M365 Security Posture Scanning 101](https://ercan.cloud/checking-cloud-with-cloud-m365-security-posture-scanning-101/): Your Microsoft 365 tenant is cloud infrastructure and it drifts. A 101 on posture scanning with CIS, EIDSCA, and CISA ScuBA, and why the scanner is SaaS too. ### Resilience - [AZ Isolation Held. Your Architecture Didn't.](https://ercan.cloud/nothing-fails-alone-part-1-az-isolation-held/): A cooling failure killed racks in one us-east-1 zone and a quorum died with them. What the blast radius promise covers, plus a read-only detector for it. - [Two Zones, Eighteen Hours, One Cause](https://ercan.cloud/nothing-fails-alone-part-2-two-zones-one-cause/): Drone strikes put AWS's me-central-1 region into months of recovery and its DR advice was: restore into Europe. Plus a lab mapping AZ names to real IDs. - [The Fix Shares Fate With the Outage](https://ercan.cloud/nothing-fails-alone-part-3-fix-shares-fate/): Lambda 2023, the DynamoDB DNS event, Azure's February control-plane failure: why recovery paths die with the incident, and a lab that measures static stability. - [Testing the Assumption Nobody Tests](https://ercan.cloud/nothing-fails-alone-part-4-testing-the-assumption/): AWS FIS can fail a zone and only approximate losing the control plane. How to run the game day, what to measure, and an honest scorecard for the series. ## Series - [Nothing Fails Alone](https://ercan.cloud/series/nothing-fails-alone/): A four-part DR incident analysis. Every DR plan rests on two assumptions nobody tests, that zones fail independently and that the control plane answers when you need it. 2026 tested both. All four parts in reading order. ## Other resources - [ercanermis.com](https://ercanermis.com): Hub site with about and contact. - [ercan.ai](https://ercan.ai): AI/ML writing by the same author. - [Aether365](https://aether365.io/): The author's product. AI-powered M365 Security scanning mapped to CIS, EIDSCA, and CISA ScuBA. Read-only by default; AI Pilot opt-in remediation and Business Impact Reports.