Jan Reilink

In my day to day work, I’m a systems administrator - DevOps / SRE and applications manager at Embrace - The Human Cloud. At Embrace we develop, maintain and host social intranets for our clients. Provide digital services and make working more efficient within various sectors. Read why we can use your help and support ❤️

Windows Server

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Free up disk space in Windows Server - 5 extra methods

In this post I provide you with 5 ways to cleanup files and free up disk space in Windows Server 2016 (and older / newer Windows Server version), without using the Disk Cleanup Utility. Reclaim lots of lost gigabytes easy. Disk space usage is still an issue in Windows Server.

Windows Server

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List all MAC addresses of all Hyper-V Virtual Machines

You sometimes need to list and get all MAC addresses of all Hyper-V virtual machines in your network. Either for your Hyper-V administration or provisioning if you don't set an unique MAC address automatically. Here is how to get all those MAC addresses easily with PowerShell.

Security

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"How we broke PHP, hacked Pornhub and earned $20,000"

It all started by auditing Pornhub, then PHP and ended in breaking both… We have gained remote code execution on pornhub.com and have earned a $20,000 bug bounty on Hackerone. We have found two use-after-free vulnerabilities in PHP's garbage collection algorithm. Those vulnerabilities were remotely exploitable over PHP's unserialize function.

High Performance MySQL

GNU/Linux

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MySQL InnoDB performance improvement: InnoDB buffer pool instances - Updated!

Are you running into MySQL load problems? InnoDB Buffer Pool optimization is an important step in tuning MySQL servers for heavy InnoDB workloads. Configuring innodb_buffer_pool_instances and increase read/write I/O threads. Dividing the InnoDB buffer pool into multiple instances can improve Disk I/O. And by doing so, you run your database & server more efficiently and faster. Here is a little help for you.

IIS URL Rewrite Module error: IIS Version 7.0 or greater is required to install IIS URL Rewrite Module 2.

Windows Server

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How to install IIS URL Rewrite Module on Windows Server 2016 & IIS 10

When you start to play with Windows Server 2016 and IIS 10, you'll get an error when you try to install the IIS URL Rewrite Module in IIS. The error occurs because the URL Rewrite Module installer contains an invalid version check for the IIS being used. Here is how to install IIS URL Rewrite Module 2 in IIS 10...

WordPress logo

WordPress

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17+ Useful WordPress snippets

Small PHP snippets for functions.php or a site-specific plugin: WordPress filters, actions and functions to add the functionality you need.

Swiss Army knife, a red and silver multi tool

Windows Server

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AppCmd introduction and examples

The AppCmd.exe command is your one-stop-shop for administering Windows Server IIS web servers. In combination with WinRM it is your Swiss Army knife for your daily routine. This post introduces appcmd and provides you with a lot of helpful appcmd examples.

Security

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Cracking PHP rand()

A very interesting read about how PHP rand() works, how to attack and crack it, and why you must not use it for security tokens.

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