![8vl3onvznkopxa6ny9995yrc4gw[1]](https://i0.wp.com/www.krazyworks.com/wp-content/uploads/2021/10/8vl3onvznkopxa6ny9995yrc4gw1-175x150.jpg "Awk & sed Snippets for SysAdmins")
Books have been written on the subject of awk and sed. Here’s a small sample of commands I put together over the years that are useful for everyday system administration tasks. Most of these tasks …
Read the full story »Restart Apache, MySQL When Low on Memory
Heavy traffic, hungry SQL queries, leaky applications will eventually leave your server low on memory. Apache will go on a hunt for swap space and MySQL will start freezing in thoughtful contemplation. Your hard drives …
MySQL Global Search and Replace Script
A day will eventually come when your need to find and replace a string of text in your database. You don’t know which row, or which column, or which table. Heck, you may not even …
Passing MySQL Commands from Shell Script
Running MySQL commands from a shell script is a relatively simple task that has a lot of people baffled. Some say its too complicated and suggest using PHP or Perl, others claim doing so is …
WordPress Directory Listing Risk
A large number of WordPress directories do not have an index file. This is particularly dangerous in case of the plugins directory. If your server allows directory listings, a potential attacker may see which plugins …
DownThemAll! “No free space” error
DownThemAll! is a popular download manager for Firefox Web browser supporting multi-part downloading with ability to pause and restart downloads without losing data. A common problem encountered while using DownThemAll! is the dreaded “no free …
Controlling Process CPU Utilization
Let’s say there is a process on your Unix/Linux system that sometimes tends to consume all CPU resources and become unresponsive. At the same time, you do not want to terminate the process at the …
Encoding Videos for XBox 360 and PS3
Both Xbox 360 and PS3 support a variety of video codecs and are capable of playing high-definition video files. One of the most popular formats for HD video files is Matroska (MKV), which provides excellent …
Linux and High I/O Wait
When you look at the CPU activity of your computer, one of the parameters is the iowait. This value shows how much time your CPU wastes while it is waiting for I/O operations for complete. …
Sharing Videos from Linux to Xbox 360
Xbox 360 uses UPnP protocol to stream multimedia files from computers on your home network. Normally, you would have a Windows PC running WMP and sharing files. But what if you have a Linux box …
What’s the Best CMS
Content management systems are sprouting up like mushrooms after a warm April rain. If your job is to find the perfect CMS for your needs, you can spend weeks analyzing and comparing features of various …
Partitioning System Disk
When performing a new Unix OS installation you are usually presented with a choice of accepting the default partitioning layout or going into advanced settings and defining your own partitions. The default layout will normally …
Google Tips and Tricks
Google offers a remarkable set of powerful features. Unfortunately, most people are not aware of these possibilities. They use only the most basic functionality offered by Google and then waste their time on weeding out …
Convert Images to PDF
Converting sets of images into multi-page PDF files makes it easier to organize and share them. All you need for the conversion is the free that will run on your Windows, Linux, MacOS and many other operating systems. If you are running a recent version of Linux, chances are that ImageMagick is already installed on your computer (just type “which convert” to check).
Best of Web Design
As more Web surfers get high-speed access, Web designers are tempted to go overboard with multimedia sites that waste your time and distract you from the content. This little collection of Web designs is proof …
Random Filename Chooser
This is a rather peculiar little script with a purpose that may not be immediately apparent. The script will look for files in the specified folder; it will then pick one at random from the …
WordPress Quick Upgrade for Linux
Never ever upgrade WordPress to the latest version as soon as it comes out, unless you want to be the guinea pig dealing with the new bugs and incompatible plugins. Even if the new version …
Linksys WAP54G Secure Configuration
Below are some basic steps to secure a wireless access point (WAP). The screenshots are for Linksys WAP54G v. 3.04, however, the same steps will apply to wireless access points from other manufacturers. Understand this: …
Apache and Multiple Domains – from Home
Apparently there are folks out there who are still interested in running their own Web server from home. More than that – they want to have multiple domains. Guys, Web hosting these days is so …
Data Security and Online Privacy
You have information on your computer that you don’t want others to see. Sometimes you want to share information with someone, but you don’t want anyone to know that you are the one sharing it. Let’s say that you came across some information suggesting that your employer may be breaking law. You want to make this information public, but you can’t do it openly becausloe you will be fired. Another example: you are at work and you need to send a personal, confidential email…
Scali Manage (Platform Manager) CLI Guide
Scali Manage – the bloated and unpredictable HPC cluster management tool – has recently been acquired by Platform Computing Corp. It is to be integrated into Platform LSF and Platform OCS products. I can’t say …
Dealing With Disk Hogs
Some users and application developers believe that any free disk space on the server belongs to them. Suddenly you get an email alert saying that a server “xyz” ran out of disk space in /home. …
Useful SysAdmin Scripts: Search-and-Replace
Let’s say you moved your server to a new network and now it has a different IP address. You know your users have a habit of hard-coding the server’s IP into their scripts. So you …
Commands & Shells »
Awk & sed Snippets for SysAdmins
![8vl3onvznkopxa6ny9995yrc4gw[1]](https://i0.wp.com/www.krazyworks.com/wp-content/uploads/2021/10/8vl3onvznkopxa6ny9995yrc4gw1-80x80.jpg "Awk & sed Snippets for SysAdmins")
Books have been written on the subject of awk and sed. Here’s a small sample of commands I put together over the years that are useful for everyday system administration tasks. Most of these tasks …
Synology NAS Hacks
![rhd3hj6zvnqeth7qo8em0alduj0[1]](https://i2.wp.com/www.krazyworks.com/wp-content/uploads/2021/10/rhd3hj6zvnqeth7qo8em0alduj01-80x80.jpg "Synology NAS Hacks")
I’ve been using various Synology NAS devices for many years now, and they’re great. Well, almost. There are a few rough spots that don’t thrill me. These consumer-grade devices are designed to be difficult to …
Applications »
Synology NAS Hacks
I’ve been using various Synology NAS devices for many years now, and they’re great. Well, almost. There are a few rough spots that don’t thrill me. These consumer-grade devices are designed to be difficult to …
WordPress: Post-processing of the image failed
![ytioq398kc1wnvvz95uixhcn5ii[1]](https://i2.wp.com/www.krazyworks.com/wp-content/uploads/2021/08/ytioq398kc1wnvvz95uixhcn5ii1-80x80.jpg "WordPress: Post-processing of the image failed")
This particular WordPress issue appeared with version 5.3 and is refusing to go away. However, the problem here is not with WordPress but with the Apache ModSecurity. The particular ModSecurity rule in question is 200003 …
Data »
Synology NAS Hacks
I’ve been using various Synology NAS devices for many years now, and they’re great. Well, almost. There are a few rough spots that don’t thrill me. These consumer-grade devices are designed to be difficult to …
Finding Duplicate Photos
![9dwz62kvm0gtjya9kwb7pawtk9y[1]](https://i2.wp.com/www.krazyworks.com/wp-content/uploads/2021/10/9dwz62kvm0gtjya9kwb7pawtk9y1-80x80.jpg "Finding Duplicate Photos")
Being a shutterbug and a digital hoarder can get expensive. A couple of days ago, my
TerraMaster D5-300 5-bay DAS crashed. Again. This time it was the power supply. I replaced it only to discover that …
Monitoring »
NFS I/O Stats with Logging
![tq9mhhd5xy2q0kto2j1785n6odv[1]](https://i1.wp.com/www.krazyworks.com/wp-content/uploads/2021/10/tq9mhhd5xy2q0kto2j1785n6odv1-80x80.jpg "NFS I/O Stats with Logging")
The nfsiostat is an excellent tool for analyzing NFS performance. The only major problem with this utility is that it’s designed to be used interactively. It does not have logging or timestamping capabilities. I needed …
Finding Cron Jobs
![iwoau71okwxqh4jv3k4ook32qps[1]](https://i2.wp.com/www.krazyworks.com/wp-content/uploads/2021/08/iwoau71okwxqh4jv3k4ook32qps1-80x80.jpg "Finding Cron Jobs")
Cron is an indispensable tool for system administration. The difficulties in working with cron in a large environment stem from its decentralized nature. Cron jobs multiply like rabbits, and keeping track of them is not …
Networking »
NFS I/O Stats with Logging
The nfsiostat is an excellent tool for analyzing NFS performance. The only major problem with this utility is that it’s designed to be used interactively. It does not have logging or timestamping capabilities. I needed …
Inventorying NFS Mounts and Mount Options
![4ucne6vs8m7hqdl0el9ddqd1sql[1]](https://i2.wp.com/www.krazyworks.com/wp-content/uploads/2021/10/4ucne6vs8m7hqdl0el9ddqd1sql1-80x80.jpg "Inventorying NFS Mounts and Mount Options")
As time goes by, NFS mounts multiply like rabbits. Added by many different people over the years, these entries present a dizzying variety of mount options – most are a copy-paste job that makes little …
Editor
Igor
Sr. Unix SysAdmin with twenty years experience supporting Solaris, HP-UX, AIX, IRIX, and Linux servers in a large distributed environment.
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