SSL Certificates Are Expiring Faster: Every Change Through 2029
SSL certificate lifetimes drop to 200, 100 and then 47 days by 2029, and Let's Encrypt moves to 45 days. What changes when, and how to stay ahead.
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Browse all tutorials →Avoiding SSL Certificate Problems Before They Break Your Site
Why SSL certificates fail (expiry, revocation, hostname mismatch) and how to monitor them automatically so they never break your site or your users' trust.
Easy VPN Setup with WireGuard Manager
Set up a WireGuard VPN in minutes with wireguard-manager, a free script for Debian and Ubuntu: install, add or remove clients and generate mobile QR codes.
Mastering OpenStack: A Beginner’s Guide Video Series
A 5-part OpenStack video series for beginners: install it on Ubuntu in VirtualBox, launch instances, set up networking and SSH, upload images, use the CLI.
Getting Started with Linux: Understanding Relative and Absolute Paths
Understand absolute and relative paths in Linux with clear examples: what /, ., .. and ~ mean, how to use them with cd and cp, and when to use each one.
Getting Started with Linux Command Line: 10 Commands Everyone Must Know
New to the Linux command line? Learn the 10 essential commands (ls, cd, pwd, mkdir, rm, cp, mv, cat, sudo and man) with simple examples and bonus tips.
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