100 Server and Application Performance Monitoring Tools 2019

Last Updated: Jan 15th 2019 November 29th 2018 – Site24x7 replaces Coscale. Coscale was recently acquired by New Relic.  Oct 11th 2018 update: 100+ – Fixed 11 broken links. (including defunct, mergers, acquisitions, or changed links) December 1st 2017 update: 70 100 Top Server Monitoring & Application Performance Monitoring Tools. August 6th 2017 update: 50 70 Top Server Monitoring & Application Performance Monitoring […]

Could not increase number of max_open_files to more than… (Solution)

A quick solution to the warning “Could not increase number of max_open_files to more than” when starting MySQL or MariaDB. For some background read How MySQL Opens and Closes Tables. Here’s an excerpt: “The table_open_cache and max_connections system variables affect the maximum number of files the server keeps open. If you increase one or both of these […]

20 Top Server Monitoring & Application Performance Monitoring Solutions

UPDATE: 50 Top Server Monitoring & Application Performance Monitoring (APM) Solutions Last Updated: Nov 23th 2018 – Fixed broken links. (including defunct, mergers, acquisitions, or changed links) Back in September I wrote about an article than touched on the subject of server performance monitoring.  Then just last month a LinkedIn connection asked: “I am using New Relic to monitor […]

Measure Linux web server memory usage correctly

Important update: This article was originally posted back in 2014. However, as I later posted in 2017 in the blog post Does your Linux server need a RAM upgrade? Lets check with free, top, vmstat and sar …there was a Linux kernel change to address this in 2016. Hopefully, this change will motivate New Relic and others to follow […]

MySQL Query Cache for Performance, Avoid This When Tuning

Update: MySQL query cache is deprecated as of MySQL 5.7.20, and is removed in MySQL 8.0. – mysql.com One of the most misconfigured MySQL performance features, is MySQL query_cache_size. This post references a web server with 32 gigabytes of RAM where the existing config had MySQL’s query cache size set incorrectly to 4 gigabytes. The thought behind it seemed […]

Replacing Cloudflare with CSF Firewall

November 5th 2018 update: I’ve updated this article (the install URL and other minor fixes/improvements). I replaced Cloudflare and thus also Cloudflare Argo with KeyCDN + local firewall and server hardening for this blog as of June 2018. However, do support clients who use Cloudflare and still highly recommend it.  2017 update: With the recent Cloudflare “Cloudbleed” data leak. […]

htop: Here’s how to customize it

htop is an interactive system-monitor, but also a process-viewer, process-manager, strace tool and more. Sysadmins may opt to use htop in cases where Unix top does not provide enough information about system processes. htop uses a cursor-controlled interface for sending signals to processes. Just one example where this comes in handy: you don’t have to type […]

How to Kill Inactive SSH Sessions

So, you’ve been disconnected from your server a couple of times which resulted in inactive ssh sessions. You know this because when you use the “w” command, you see something like the following… 22:47:28 up 315 days, 21:09, 2 users, load average: 9.04, 8.17, 7.30 USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT root pts/0 ipxxx-xxx-xxx-xxx 23:54 […]

Linux: ncdu and mc to manage large directories

Creating, modifying and deleting files are common tasks performed in any operating system. Even more so by Sysadmins, Developers and Programmers. For the most part, these tasks are fast enough when managing a handful of files. However, on Linux and especially with servers, you may at sometime have to manage millions or even billions of […]

Choosing the Best Linux Server Distro

Are you trying to decide on a Linux server distro (distribution)? This article will help guide you based on the strengths of the Linux server distributions available. If you are looking for desktop advice, have a look at Choosing the Best Linux Distro for Desktop.   Best Linux Server distro The first rule to remember when […]