Welcome

Pacific Simplicity is the home to my tech blog of sorts, aiming to assist and provide information easily to other Linux users and Open Source hackers out there.  It contains articles on Linux, system admin hints, scripting, programming embedded systems, OpenWRT and of course Drupal . Check it out and don't forget to comment!

Verified Boot – Introduction to U-Boot’s Secure Boot
Posted: Sun, 09/24/2017 - 13:37

First things first, Uboot for the uninitiatited is an open source bootloader that is commonly used on Linux ARM, and MIPS systems, but has roots in the PowerPC (PPC) days. It supports a number of computer architectures and is secretly hiding away in many devices you or I use everyday (e.g., home routers).

A few notes about CPU load and resource consumption
Posted: Tue, 07/11/2017 - 12:39

A few observations about looking at TOP that I hear people asking are regarding what does the % mean, and why can I have over 100% when looking at CPU usage.

Well, its sort of simple. Load averages are the average of the load number for a process in a given period of time. A load number is merely a metric that is an average that takes into account CPU usage (or consumed time-slices) by the process. These could be:

Quick script to generate XML for each network interface
Posted: Sat, 02/11/2017 - 20:59
#!/bin/bash
# @file statistics.sh
# @author Ron Brash (<a href="mailto:[email protected]">[email protected]</a>)
# @date Jan 2017
# @purpose Collect network interface statistics and other information and output
# it in XML format instead of arbitrary formatting
#

PATH_DIR=/sys/class/net
INTF_WILD="e*"

Bypassing U-Boot Partition Read-only Permissions/masking by Chain-loading Uboot
Posted: Wed, 01/18/2017 - 10:17

Recently, we had to bypass a bootloader that had partition permissions and we needed to overwrite u-boot. Unfortunately, writing to this section of flash was not possible (invalid permissions/read-only), BUT, we could TFTP our own u-boot binary image to the device.

Epoll /dev/input keyboard press example
Posted: Wed, 01/11/2017 - 08:41

Here is a simple epoll example for polling keyboard events:

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