How To Get A Reverse DNS Lookup On The Command Line

Author: , September 1st, 2021

There are three commands in Linux to easily get a reverse DNS lookup with: dig, host and nslookup. Here are examples of each: shell> dig -x +short

shell> dig -x

shell> host

shell> nslookup

Slick Command-Line Tricks for a Tungsten MySQL / MariaDB Database Cluster

Author: , July 16th, 2019

Tungsten Clustering provides high availability, disaster recovery, and a host of other benefits for MySQL / MariaDB / Percona Server databases. In this blog post we will explore some of the shell aliases I use every day to administer various Tungsten Clusters.

How To Test Nagios Remote NRPE Commands

Author: , September 27th, 2018

There are many things to configure in Nagios, especially when using custom check commands. Recently I needed to configure all of the Continuent Clustering Nagios checks. Once setup on the database side, I wanted to confirm that everything was working. Basics: Run a Remote NRPE Check To test a remote NRPE client command from a […]

How To get haproxy status via socket using cli

Author: , October 6th, 2017

echo “show stat” | nc -U /var/lib/haproxy/stats | cut -d “,” -f 1,2,5-11,18,24,27,30,36,50,37,56,57,62 | column -s, -t

How To Reduce the Size of a PDF Using Ghostscript

Author: , February 4th, 2017

Make sure you have Ghostscript installed, then:

-dPDFSETTINGS={value} where {value} is one of: /screen – the lowest resolution and lowest file size, fine for viewing on a screen /ebook – mid-range resolution and file size /printer – high-quality setting used for printing PDFs /prepress – high-quality setting used for printing PDFs As always, YMMV…

How To Send Email From the Command Line on MacOSX 10.10.5 Yosemite

Author: , January 29th, 2017

I wanted to send email from cron for various reasons, but the emails would bounce with an error 554: 554 5.1.8 : Sender address rejected: Domain not found Clearly, Postfix was using the “internal” hostname of myappledesktop.local (MacOSX has TWO hostnames! also, myappledesktop.local is not the real hostname ;-). So, I needed two things: 1. […]

How To Install a .pkg file from the Command Line on MacOSX

Author: , August 12th, 2016

sudo /usr/sbin/installer -pkg /path/to/yourFile.pkg -target /

How To Create a PDF from Multiple Image Files on the Command Line

Author: , June 6th, 2016

convert myFile*.jpg myFile.pdf convert myFile*.png myFile.pdf

How To Eject a Volume from the Terminal Command Line in MacOSX

Author: , December 8th, 2015

As always, YMMV…

How To Convert UNIX Timestamps to Date using PHP CLI

Author: , August 15th, 2015

For a quick visual check to see what the human-readable date is based on a UNIX timestamp integer: php -r ‘print date(“r”,1483228799);’ php -r ‘print strtotime(“1 Jan 2015”) – 1;’