Tag: Linux

Oct 10, 2026 ·

Asif Mughal · 61

Docker Ignores Your UFW Rules. Here's How to Check Your Own Server

Docker writes its own firewall rules, so UFW can say a port is blocked while a container port stays open to the internet. Here is how to check your own server and fix it three ways.

Sep 18, 2026 ·

Asif Mughal · 115

Nginx Shows 502 But Your App Is Running? Check This IPv6 Localhost Trap

Nginx shows 502 Bad Gateway but your app is confirmed running? Check for an IPv4 vs IPv6 localhost mismatch in proxy_pass. Here is how to spot it in the error log and the one-line config fix.

Sep 7, 2026 ·

Asif Mughal · 77

Why mysqldump Says "Deprecated Program Name" (and How to Fix Your Backup Script)

If your backup script suddenly shows a "Deprecated program name" warning, you're probably running MariaDB, not MySQL. Here's why mysqldump is being renamed and how to update your backup script before it actually breaks.

Sep 3, 2026 ·

Asif Mughal · 97

Ubuntu 26.04 LTS Needs a Newer CPU. Check This Before You Upgrade Your VPS

Ubuntu 26.04 LTS cloud images now require a newer x86-64-v3 CPU baseline, and older or budget VPS hardware may not qualify. Here is the one command to check before you upgrade, and why a failed upgrade is worse on a remote server than a desktop.

Aug 30, 2026 ·

Asif Mughal · 100

Too Many Certificates Already Issued for Exact Set of Domains

Too many certificates already issued for exact set of domains means you hit Let's Encrypt's 5-per-week duplicate limit. Here is why shorter certificate lifetimes make this more likely, and the real fix, not the advice that makes it worse.

Aug 29, 2026 ·

Asif Mughal · 134

Let's Encrypt Certificates Are Getting Shorter. Is Your Renewal Script Ready?

Let's Encrypt is shortening its certificate lifetimes, moving from 90 days down to 64 days by February 2027, with 45-day and even 6-day options already available. If your renewal script still assumes a 30-day buffer, here is why that assumption is starting to run out of room.

Aug 29, 2026 ·

Asif Mughal · 310

Why Your Sudoers Rule Stopped Working on Ubuntu 26.04 (sudo-rs Wildcard Change)

Ubuntu 26.04 LTS quietly made sudo-rs the default sudo. If your sudoers rules use a wildcard inside command arguments, they will silently stop matching. Here is what changed and how to fix it.

Aug 29, 2026 ·

Asif Mughal · 96

Locked Out of Your VPS After Enabling UFW? Here's the Fix (and How to Avoid It)

Enabling UFW without allowing SSH first is one of the most common ways people lock themselves out of a VPS. Here's the correct order, the gotcha if you've changed your SSH port, and how to recover if it's already happened.

Aug 28, 2026 ·

Asif Mughal · 72

Your Backup Script Can Fail Silently — Here's How to Actually Find Out

Restic backups fail silently more often than loudly — a flaky network, an expired token, a full disk — and cron won't tell you. Here's how to wire a self-hosted Healthchecks dead man's switch into a restic backup script, and the single setup mistake that quietly defeats the whole point.

Aug 28, 2026 ·

Asif Mughal · 112

Fix "mysqldump: Access denied... (using password: NO)" in an Automated Backup Script

Your mysqldump command works when you type it yourself but fails from cron with "Access denied... using password: NO"? Here's the actual cause (it's not your password) and the right fix for an automated backup script.

Aug 27, 2026 ·

Asif Mughal · 101

VPS Running Out of Memory? How to Set Up Swap Properly (and Fix the Real Cause)

A small VPS running out of RAM is one of the most common ways WordPress and Laravel sites go down. Here's how to size and set up a swap file properly, tune swappiness, and fix the MySQL setting that's usually the real cause.

Aug 25, 2026 ·

Asif Mughal · 96

How to Disable SSH Password Login on a VPS (And Make It Actually Stick)

Disable SSH password login and switch to key-only authentication on a VPS — including the cloud-init config override that silently breaks this on most guides.