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CSS Container Queries: Responsive Components by Their Own Size

PHP cURL Error 28: Find Where the Request Times Out

Verify a Downloaded File with SHA-256 on Windows and Linux

A Website Opens on Other Devices but Not One Computer

Changed PHP in cPanel but the Old Version Still Runs?

WHM Apache Status Fails While Apache Is Running: What to Check

Linux Server Performance: Measure Before Tuning

Nginx and Apache Security: Review the Whole Request Path

GitLab Updated but Still Vulnerable? The Alpine Incident and Ruby Checks

Is Logrotate Working? Check Scheduling, Rotation and the Active Log

Linux Is Logrotate Working? Check Scheduling, Rotation and the Active Log

A growing log sits beside several .gz archives. That does not establish that logrotate worked today. Those archives could be old, and the application ...

MySQL Server Has Gone Away: Packet Limit or a Stale Connection? Image

Databases MySQL Server Has Gone Away: Packet Limit or a Stale Connection?

“MySQL server has gone away” sounds like the database stopped entirely. Sometimes it did. Sometimes the application simply tried to reuse an expired c...

Website Works over IPv4 but Not IPv6: Look Beyond the AAAA Record Image

Networking Basics Website Works over IPv4 but Not IPv6: Look Beyond the AAAA Record

A website loads at home but hangs on a phone connection. Its A record looks correct and the server is running. One useful next check is the IPv6 path....

PHP PHP cURL Error 28: Find Where the Request Times Out

An API request normally finishes in a second, then intermittently fails with cURL error 28. Increasing the timeout is tempting. But a slow DNS lookup ...

Cyber Security GitLab Updated but Still Vulnerable? The Alpine Incident and Ruby Checks

The GitLab upgrade finished and the version number looks right. Has the vulnerability actually gone away? Alpine Linux's incident is a useful reminder...

PHPDoc Annotations: When to Use @param and @return Image

PHP PHPDoc Annotations: When to Use @param and @return

Comments are useful until they merely restate the next line of code. PHPDoc is more valuable when it records a function's contract: what callers must ...

Undefined Array Key in PHP 8: Handle Missing Fields Image

PHP Undefined Array Key in PHP 8: Handle Missing Fields

After moving to PHP 8, your logs may start showing Undefined array key warnings. Often the code assumes that every request contains a field that is ac...

PHP include Failed to Open Stream: Fix the File Path Image

PHP PHP include Failed to Open Stream: Fix the File Path

include(): Failed to open stream, often followed by Failed opening required, does not necessarily mean the file was deleted. PHP may simply be resolvi...

Composer Class Not Found: Check PSR-4 Paths and Case Image

PHP Composer Class Not Found: Check PSR-4 Paths and Case

Composer finishes installing dependencies, but the application reports Class "App\\Service\\MailSender" not found. The package may be present; the aut...

Before Upgrading PHP: A Practical Application Checklist Image

PHP Before Upgrading PHP: A Practical Application Checklist

Changing PHP in a hosting panel takes seconds. Finding the overlooked failure can take much longer: the home page loads, but login breaks, uploads fai...

PHP Upload Limits: upload_max_filesize vs post_max_size Image

PHP PHP Upload Limits: upload_max_filesize vs post_max_size

If a PHP upload form works with small files but returns an empty $_FILES for larger ones, separate two limits before changing application code. upload...

PHP 8.5 Features: Practical Examples You Can Run Image

PHP PHP 8.5 Features: Practical Examples You Can Run

Cleaning a string often means calling several functions in sequence. Changing part of a URL can mean rebuilding it by hand. PHP 8.5 adds tools for exp...