![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 »General Service Request
A formal way to submit a service request is to fill out one of the forms below. Your request will be assigned a number and an analyst will contact you shortly. You must have a valid support contract to submit a service request. Please select a form that appears most appropriate for the problem you are experiencing. If you don’t see an appropriate match, please use the General Service Request.
Highly redundant array configuration
The cost of storage arrays is falling along with the quality of their manufacture. To quote Lev Andropov from the “Armageddon”: “Components. American components, Russian Components, ALL MADE IN TAIWAN!” What in the nineties used …
Improving WordPress Performance
WordPress is a great blogging engine and decent CMS. Unfortunately, most available WordPress themes- even those claiming to be “minimalist” – are bloated and slow to load. Heavy CSS stylesheets, multiple Java scripts, numerous graphics …
Use Perl inside Shell scripts
Perl is a far more powerful programming tool than any shell script. Sometimes you want to borrow some of that power without having to rewrite your entire shell script. There is an easy way to integrate Perl snippets inside your shell script.
Computers Kill
Computers kill. That’s right: according to the National Highway Traffic Safety Administration, some 2,600 die every year in car accidents because they got distracted by their cell phone, a GPS gadget, an MP3 player, or …
AI Research: Playing Mind Games
The news of Artificial Intelligence research always attracted my attention. I myself was a fan of new technology, especially I am a gamer as well and my friends, looting and trading diablo 2 items for …
Your unsecured Wi-Fi network
Network World reports this week that, according to a study by Accenture, some twelve percent of computer users are connecting to some else’s unsecured Wi-Fi networks. So here’s the question I wanted to discuss: is …
Convert MySQL table to CSV file
CSV is a field-separated format that can be easily imported into a spreadsheet application. Usually the separator field is a comma. However, sometimes it is easier to select a more unusual character (like “@” for …
Installing and Configuring Ganglia
Ganglia is a distributed performance monitoring application used primarily for tracking status of high-performance compute (HPC) clusters. Ganglia is a royal pain in the ass to install and configure even for a seasoned Unix sysadmin. …
Dealing with ReiserFS bad blocks
The following is a procedure for recovering a ReiserFS filesystem with bad blocks. If this is a system FS and cannot be unmounted, the box needs to be booted from the latest version of Knoppix …
ReiserFS Filesystem Recovery
The this is a description of a method for recovering ReiserFS filesystems from failed disks with bad blocks, when other recovery methods (reiserfsck) will not work. For this example, the failed server is called node1 …
Log Monitoring with Swatch
Swatch is a Perl-based log monitoring tool that can match regular expressions and perform automated actions. The tool is useful for monitoring system log files in real time with an option to run external commands …
Linux User Activity Management
The following is a detailed look into managing Linux users and the system resources they utilize. Disabling user access; halting, killing, and re-nicing user processes; controlling disk space allocation are all points covered by this …
Veritas Cluster Troubleshooting
Veritas cluster server is a high availability server. This means that processes switch between servers when a server fails. All database processes are run through this server – and as such, this needs to run smoothly. Note that the oracle process should only actually be running on the server which is active.
Veritas HSM Maintenance
When resizing a VXFS filesystem on a server that has HSM running, it is necessary to place HSM in maintenance mode for that particular filesystem. Failing to do so may cause the VFS resize operation …
Protected: SuSE Mail Transfer Agent Configuration
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Korn Shell Arrays
Here are a few useful examples of how to use data arrays within Korn shell. Arrays are a great tool for storing user input and other data for quick, on-the-fly access. If, for example, you …
A simple text string search script
Sometimes you need to locate a text string in various configuration files. You don’t know which files. You can just use “grep *”, but the output is rather messy and you can only search in …
Upgrade procedure for phpBB2
The following is an example procedure for upgrading phpBB2 bulletin board software running under Linux. This procedure allows to retain forum customization.
Download “Changed files only” package from http://www.phpbb.com/downloads.php
Tar cvf and gzip the entire phpBB2 installation …
Commands & Shells »
Plundering Facebook Photo Albums
![wyryr1sn52gntzn65v4fpz5lc6v[1]](https://i2.wp.com/www.krazyworks.com/wp-content/uploads/2021/08/wyryr1sn52gntzn65v4fpz5lc6v1-80x80.jpg "Plundering Facebook Photo Albums")
Let’s imagine you need to download all the photos in a Facebook photo album. It can be a public album, a friend’s, or even your own. Sure, you can do this manually, but you probably …
Scraping a Web Page in Bash
![clfud46mxf2t5zph2l04zlpgl1d[1]](https://i2.wp.com/www.krazyworks.com/wp-content/uploads/2021/08/clfud46mxf2t5zph2l04zlpgl1d1-80x80.jpg "Scraping a Web Page in Bash")
Just a scripting exercise because I need to do something important, but I am procrastinating. The idea is simple: grab some URL with text containing somewhat structured data and convert it into a spreadsheet. I …
Applications »
Processing Videos with ffmpeg and Lightroom
![DSCF5361[1]](https://i1.wp.com/www.krazyworks.com/wp-content/uploads/2020/10/DSCF53611-80x80.jpg "Processing Videos with ffmpeg and Lightroom")
On occasion I wondered how to apply advanced photo filters to my lackluster GoPro and drone videos. You know, not the basic exposure/contrast/saturation or the cheesy special effects you find in video editors, but something …
Searching Twitter
![Cat-Devouring-A-Bird-Pablo-Picasso[1]](https://i0.wp.com/www.krazyworks.com/wp-content/uploads/2020/10/Cat-Devouring-A-Bird-Pablo-Picasso1-80x80.jpg "Searching Twitter")
Here are just a few hopefully useful tips for searching Twitter to get more relevant results and buy cheap twitter followers.
Data »
Scraping a Web Page in Bash
Just a scripting exercise because I need to do something important, but I am procrastinating. The idea is simple: grab some URL with text containing somewhat structured data and convert it into a spreadsheet. I …
Generating Random Text Files for Testing
![91ebozy1e3b138waujy28agrngy[1]](https://i2.wp.com/www.krazyworks.com/wp-content/uploads/2021/08/91ebozy1e3b138waujy28agrngy1-80x80.jpg "Generating Random Text Files for Testing")
Sometimes you need dummy folder structures populated with random data for testing your various scripts and processes – backups, file transfers, encryption, compression, etc. Every time I need something like this, I end up writing …
Monitoring »
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 …
Understanding Memory Utilization in Linux
![5gtysva4wkc8mzc1k3e66vaycxx[1]](https://i1.wp.com/www.krazyworks.com/wp-content/uploads/2021/08/5gtysva4wkc8mzc1k3e66vaycxx1-80x80.jpg "Understanding Memory Utilization in Linux")
This is a depressing – and all-too-common – scenario: a user runs the free command and opens a support case because he sees zero “free” memory on the server.
Networking »
Validating HTTPS Cache Peers for Squid
![sy2zeb1vp2h8itlxfbbylw0jrm0[1]](https://i0.wp.com/www.krazyworks.com/wp-content/uploads/2019/12/sy2zeb1vp2h8itlxfbbylw0jrm01-80x80.jpg "Validating HTTPS Cache Peers for Squid")
I have a squid proxy server that uses a long list of authenticated cache peers in a round-robin configuration. The process looks something like this:
Verifying SNMP Connectivity on Multiple Hosts
![Photo-2019-10-07-14-39-03_0266[1]](https://i1.wp.com/www.krazyworks.com/wp-content/uploads/2019/11/Photo-2019-10-07-14-39-03_02661-80x80.jpg "Verifying SNMP Connectivity on Multiple Hosts")
I needed to check if SNMP was accessible on whatever live servers that existed in a particular subnet. Here’s a quick script to do this.
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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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