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September 9, 2021 – 11:28 am

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 …

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Processing Videos with ffmpeg and Lightroom

October 12, 2020 – 1:52 pm
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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

October 11, 2020 – 1:50 pm
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Here are just a few hopefully useful tips for searching Twitter to get more relevant results and buy cheap twitter followers.

Bash Scripts and MySQL

October 10, 2020 – 1:49 pm
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I frequently use MySQL to store data collected or processed by various shell scripts. The database comes in handy when massaging data with good old awk and sed gets too cumbersome.

Validating HTTPS Cache Peers for Squid

January 6, 2020 – 12:38 am
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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:

Updating PHP 5.6w to 7.1u on CentOS 6.10

December 30, 2019 – 9:53 pm
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This is mostly just a note to self. As I mentioned previously (probably more than once), I very much dislike systemd and will stick with CentOS 6 for as long as possible. Having said that, …

Windows 10 Upgrades

December 6, 2019 – 9:44 pm
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I did the only sensible thing and disabled automatic updates on my two Windows 10 laptops. Microsoft’s belated foray into the world of CI/CD for releasing Windows patches suffers from limited automated testing.

Notes on ownCloud configuration

April 12, 2019 – 4:13 pm
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The ownCloud file sharing application has been around for some time now, but somehow evaded my attention. My limited imagination makes me say “think of it us Dropbox hosted on the server in your basement”.

Removing Chef Server Installation

January 9, 2019 – 4:44 pm
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Just a quick note on how to completely remove (more or less) Chef server installation from a CentOS/RHEL box.

AWS CLI Cheat Sheet

August 14, 2018 – 4:18 pm
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The installation and configuration process for AWS CLI is fairly simple. The package itself is installed with pip (yum -y install python-pip):

Late Night Rant: Agile Apps

August 5, 2018 – 4:11 pm
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While we’re still in the middle of a pandemic, rules about going out have loosened up. But experts agree that the best way to protect yourself is to limit your interactions with other people. If …

The Mystery of a Hemisphere

July 31, 2018 – 4:00 pm
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To make this long (and embarrassing) story short: a friend’s kid had a homework assignment in geometry to calculate the surface area of a conjoined cone, a cylinder, and a hemisphere.

Useful MySQL One-Liners

November 8, 2017 – 12:16 pm
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I am by no means an expert SQL programmer. Having said that, I’ve been using MySQL for a very long time. This is a collection of simple but useful SQL queries and MySQL configuration options. …

SystemD: Back To The Future

May 23, 2017 – 8:38 pm
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A creature in its death throes, Sun Microsystems gave birth to Solaris SMF – the product of a disturbing union between Unix System V and the Microsoft Windows Registry. Shortly thereafter the proud father died, …

Get a List of all ESX Hosts in a Datacenter

April 17, 2017 – 3:18 pm
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Another simple one-liner to get a list of hostnames of all ESX servers in the vCenter. This can be useful for a number of things, specifically as input for other PowerCLI scripts.

Use PowerCLI to Change NIC Type

April 17, 2017 – 11:52 am
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This is a quick PowerCLI script that reads from a list of VM names and for each VM with network adapter type “E1000” changes it to “Vmxnet3”. Nothing fancy, no reboot is needed. MAC should …

Sample Salt Proxy Configuration for vCenter/ESX

March 20, 2017 – 4:15 pm
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The Salt proxy agent is a relatively new feature of Salt allowing to control networked devices where salt-minion cannot be installed directly. The official Salt documentation on the subject is outdated and full of syntax errors. It’s actually …

Configure and Run esxcli on Red Hat

March 20, 2017 – 3:58 pm
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The esxcli utility is used to interface with the vSphere and ESX hosts. It is a useful tool for getting to some basic VMWare functionality from Unix shell. It is also a pre-requisite for some of …

Samba Flexible Character Mapping

March 1, 2017 – 6:33 pm
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This is probably old news to most of you, but I just found out: Samba v 3.5+ has a new option for flexible mapping of filename characters. Unix filenames allow certain characters that Windows filename …

Managing VMs with PowerCLI

February 20, 2017 – 5:45 pm
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Below is a collection of useful Power-CLI one-liners (or thereabouts) that can speed up your script-writing efforts. As everything Windows, things change often and for no obvious reason, so expect to see type is deprecated and …

Copying a VM between VCenters

November 12, 2016 – 6:13 pm
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I had a little task: clone an operational VM from one VCenter to another. Normally, for such a task I would use the Standalone Converter. Unfortunately, this time I ran into an annoying SSH key …

Monitoring Solr Cores

November 1, 2016 – 10:50 pm
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The Cloud tab of the Solr Web UI is convenient, but not for monitoring purposes. Just like you, I hate XML and parsing it from shell is more convoluted that it needed to be. But …

Fixing NIC Name in Cloned VMWare Linux Machines

June 28, 2016 – 12:32 pm
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A suspected bug with certain versions of VMware ESX causes cloned Linux VMs to obtain a sequentially-number NIC. For example, if the parent VM had eth0, the clone will have eth1, and the clone of …