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April 17, 2019 – 4:51 pm

Just a quick collection of notes on – rather than a definitive guide to – setting up an SSH chroot jail on RHEL 6. The same should work on RHEL 7 and unrelated flavors. For …

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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

August 5, 2018 – 4:11 pm
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CollabNet VersionOne has released it’s 12th annual “State of Agile” report. The survey involved more than 1,400 software professionals in various roles and industries over the fourth quarter of 2017.

Only 12% responded that their organizations …

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 …

Kodi Volume Control Stops Working

May 22, 2016 – 1:01 am
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All of a sudden, when using the remote (either radio or IR), Kodi sound controls stop responding. The volume level does not change and the mute button doesn’t work. These are possible symptoms of an …

VMWare VMDK Locked Error

May 21, 2016 – 10:27 pm
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So, being a Unix admin on-call for the week, I just spent half of my Saturday fixing a dead Windows VM. Very annoying. The best I can tell, the issue occurred during the snapshot operation. …

Monitoring NetBackup Daemons

April 27, 2016 – 9:25 pm
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Here’s an example of a script you can use to monitor NetBackup server daemons in a Linux environment. The main difficulty with keeping track of these services is that there are so many of them. …

Parallel MySQL Queries

January 19, 2016 – 12:38 am
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Unlike Oracle, MySQL has no support for parallel SQL queries. A bummer for sure, in light of all the awesome multi-coreness we enjoy these days. There’ve been some attempts (1, 2) to get around this …

Tuesday Morning Rant

October 27, 2015 – 11:27 am
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So I just got around to installing CentOS 7. What a pile of shit with bugs all over it. The installation GUI completely messed up network configuration. On the first try, the network config I …

Arthemia jCarousel Number of Posts

September 4, 2015 – 3:45 am
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This is primarily just a note to myself on how to change the number of visible items in the jCarousel implementation for the WordPress Arthemia theme. Recently I finally updated to the current version and …