@izzymk

Introduction to Amazon ElastiCache SPL-80 - Version 1.6.11

Jan 16 · 9 min read · Overview This guide introduces you to Amazon ElastiCache. In this lab you will create an Amazon ElastiCache Redis node and connect to it from an Amazon EC2 instance to run commands. You will then clean up your resources by deleting the stack. Objecti...

Userdata script not getting executed while launching an instance

Jan 5 · 3 min read · Common Causes of UserData Script Failures Script Errors Syntax errors in bash/PowerShell script Missing shebang (#!/bin/bash) at script start Wrong line endings (Windows CRLF vs Unix LF) Script exits early due to set -e with non-zero exit codes ...

SSL/TLS : what is it and how it works

Jan 4 · 3 min read · How SSL/TLS Works SSL/TLS creates an encrypted tunnel between client and server through a handshake process: The Handshake Client Hello: Client sends supported encryption methods Server Hello: Server picks encryption method, sends certificate Cert...

Elasticache

Jan 2 · 4 min read · ElastiCache is AWS's managed in-memory caching service that runs either Redis or Valkey engines. Here's how it works: Core Concept ElastiCache stores frequently accessed data in memory (RAM) instead of disk, providing microsecond response times. App...

SUSE Linux Enterprise Server upgrade

Sep 24, 2025 · 4 min read · Lab Overview This lab provides step-by-step instructions for upgrading SUSE Linux Enterprise Server (SLES) through multiple versions: SLES 12-SP4 → SLES 12-SP5 → SLES 15 → SLES 15-SP3 Prerequisites Access to a SLES 12-SP4 instance Root/sudo privi...