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March 2, 2022 – 2:00 pm

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 …

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Article Archive for June 2016

Increasing Entropy Pool in Linux

June 28, 2016 – 9:48 pm
security_003

The pool of random numbers in Linux is derived primarily from user interaction (keystrokes and mouse movement). A server does not have such a source and the random pool may start running low, especially during …

Fixing NIC Name in Cloned VMWare Linux Machines

June 28, 2016 – 12:32 pm
network switch

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 …

Better ‘date’ Functionality in Solaris

June 28, 2016 – 8:53 am
HP-Greets-IBM-2

The Solaris date command does not have many of the useful features of its GNU equivalent. A workaround is to use Tcl. This requires tclsh to be installed (which tclsh). You can implement this workaround as …

Create NFS share from QNAP CLI

June 13, 2016 – 2:21 pm
qnap_nas_001

In this example we create the “test” NFS share on a QNAP NAS from CLI and export it to client_ip_01 and client_ip_02. Things to keep in mind: this only creates an NFS share – not …

A tcpdump Primer with Examples

June 10, 2016 – 11:15 am
network switch

“A tcpdump Primer with Examples”
A good overview of tcpdump functionality and syntax, complete with basic and advanced examples.

Speed Up Shell Loops Using Arrays

June 7, 2016 – 9:02 am
shell_003

Just a quick note on addressing a common issue of running redundant commands when using shell loops. Let’s say you needed to get a count of network connections to an Oracle database server for each connection …