Cloud Notes

🛠️ HashiCorp Certified Terraform Associate 🌐 What is Infrastructure as Code (IaC)? Infrastructure as Code (IaC) is managing infrastructure using code instead of manual configuration. Terraform allows users to define both low-level resources (like virtual machines, networks) and high-level resources (like DNS, SaaS features). Terraform: Creates infrastructure safely and efficiently. Tracks and versions changes. Allows incremental updates and changes through an execution plan. 🚀 Terraform Variables Variable Types Terraform supports several variable types: ...

🐧 Linux Essentials: An Easy-to-Understand Guide 📖 Index Package Management Command-Line Basics Getting CLI Help 📦 Package Management RPM-Based (YUM & RPM) YUM Commands Command Purpose Example yum update Update repos & packages yum update yum search <package> Search package yum search httpd yum install <package> Install package yum install nginx yum check-update <package> Check if package needs updates yum check-update nginx yum remove <package> Remove package yum remove nginx RPM Commands Command Purpose Example rpm -ipv <file>.rpm Install package with progress & verbose rpm -ipv nano.rpm rpm -qi <package> Query detailed info rpm -qi nano rpm -e <package> Remove package rpm -e nano Debian-Based (APT & dpkg) APT Commands Command Purpose Example apt-get update Refresh package cache apt-get update apt-cache search <package> Search for packages apt-cache search nginx apt-get install <package> Install package apt-get install nginx apt-get remove --purge <package> Remove package & config files apt-get remove --purge nginx dpkg Commands Command Purpose Example dpkg -i <file>.deb Install Debian package dpkg -i nginx.deb dpkg --get-selections List installed packages dpkg --get-selections dpkg --purge <package> Completely remove package dpkg --purge nginx 💻 Command-Line Basics Shell and Environment Interactive Shell: CLI session. Non-Interactive Shell: Background scripts/processes. # Check current shell echo $SHELL # Command history history # Show all commands history 10 # Last 10 commands !10 # Execute command #10 !! # Repeat last command ^typo^fix^ # Fix typo in previous command Basic Linux Commands Command Usage cd Change directories (e.g., cd /home) ls -la List files detailed, including hidden files top View active processes whoami Display current user Command-Line Syntax Command Structure: <command> [options] [arguments] Example: ...

🚀 AWS Solutions Architect Associate 🌍 AWS Global Infrastructure Regions: Geographic locations (e.g., US East, EU Central). Availability Zones (AZs): Physically isolated data centers within regions (min. 2 per region). Edge Locations: Cache points for quicker data access globally. 🌐 Route53 Amazon’s scalable DNS and Domain Name Registration service. DNS Record Type Description SOA Start of Authority A IPv4 address record CNAME Alias to another domain MX Mail exchange record PTR Reverse DNS lookup NS Name Server record Alias AWS specific enhanced CNAME Routing Policies Simple: Basic DNS routing. Weighted: Traffic split by percentage. Latency-Based: Optimal latency routing. Failover: Active-passive setup. Geographical: Routing based on user location. Geographical Proximity: Advanced geo-routing with bias. Multivalue Answer: Simple with health checks. 🔐 IAM (Identity and Access Management) Controls AWS resource access. ...

Cloud Computing On-demand delivery of IT resources. Can scale up and down based on needs. Fosters agility (number one reason why customers switch to cloud computing): Speed (global reach), experimentation (operations as code, templated environments with CloudFormation) and culture of innovation (experiment quickly with low cost) Region vs Availability Zone (AZ): Region is a physical location in the world which contains multiple AZs. AZs contain one or more discrete data centers with independent resources and housed in different facilities. Using Auto Scaling and ELB, scale up and down and only pay for what you use. Ability to deploy systems in multiple regions (lower latency) Ability to choose the region where data is stored AWS is responsible for data center security Security policy can be formalized (as code) Ability to recover from failures Core Services Global Infrastructure: ...