PROBLEM

You've got a set of devices but their names, such as NIC / Network card names keep changing on each reboot or reconnect.  This is a continuation of Linux Networking: device eth0 does not seem to be present, delaying initialization.  where we resolved a similar issue due to naming but here we'll make it persistent using this simple naming system for Linux.  At the end of this very short post, we'll have a constant name for our physical device on reboots.  In particular, it is to make the line ip link set dev wlan1 name wlan0 permanent across reboots.

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This is a quick and dirty AWK tutorial demonstrating the most common usages and features that one can use on a daily basis by human beings.  Three variants: AWK standalone, integrated into ksh, and one-liner are provided. 

On my system, AWK pointed to GAWK.  GAWK has an expanded command set but here we will only focus on specific to AWK.

AWK is a powerful language rarely used beyond printing a few columns but often can stack up better in performance, then other scripting languages.  AWK can also make for a relatively easy learn due to it's small set of functions.  This is similar to C without the complexities of such things as pointers:

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Just happened to have forgotten a password for one of my user accounts on my workstation and remembered a handy little thing one can do to reset a pass.

If you have root access, one can simply regenerate the MD5 hash with:

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This is a simple howto tutorial for creating and bonding three interfaces, a wireless one (wlan0), one RealTek based GIGe cabled NIC (eth0) and another alternate Intel based GIGe NIC (eth1).  This is partially a conceptual howto since a home HTPC / Backup center probably doesn't need three separate NIC's for redundancy.  However, with recent ventures into the world of GIGe ethernet and associated issues, it does add some merit to this initiative.  The wireless NIC card (wlan0) is thrown here just to add another level of redundancy: a wireless one.

Here are the steps to configuring bonding on RHEL / SL Linux:

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In this post we'll configure network booting through PXE.  PXE stands for Preboot eXecution Environment and has been available for Network Devices (or NIC's) for some time.  Such a network boot setup has many uses in particular in OS setup and deployment.  In this post I'll introduce the steps to quickly set one up.  The only thing required is some patience, persistance and a second NIC (NIC also known as Network or Network Interface Card) card on the second PXE server together with a network cable.  Some of the benefits are:

1. The target environment where the OS will be installed does not need any external storage devices such as USB or CD/DVD drives.
2. There is no CD burning.  It is all software based.
3. Most motherboards and computers support PXE today.
4. You are not limited to a single file size limit in place on some USB devices.
5. There's no OS size restrictions.  The amount of data available to the boot software is only limited by the amount of free hard disk space on the PXE server.

These are just a few advantages that PXE has and the cost of setup, as we will see, is only time and a little patience.

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So you've lost the password to the root account.  Worst, you've had a boot password and it was the same.  Here are some instructions on how to get back into your system:

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This post is designed as a blind test, meaning its sole purpose is for testing and learning LVM functionality.  In this process we will work with an existing LVM that contains live data to grow, shrink and move it's contents around.  Before we do anything, a disclaimer is in order:

DISCLAIMER: Aside from the disclaimer already present on the site at the bottom, I do not recommend you to follow these instructions.  The exception exists where you wish to learn and test functionality on non PRODUCTION environments (ie meaning DEVELOPMENT or QUALITY ACCEPTANCE testing environments).  Using these steps puts you at risk of loosing your data.  BACKUP YOUR DATA BEFORE PROCEEDING.  By reading the below and following any steps, you are agreeing to undertake any and all risks associated with the resulting consequences of following the steps on this site and post below.

Having said that, let's begin.  First, we'll begin by getting some information and marking our LVM for change.  The goal here is to eventually resize this partition that spans the entire 1.5TB to something much smaller (around 200GB) that we can copy to a smaller part of the hard drive to free space for a new installation and VG.  NOTE: Only one hard drive will be used here to do this with:

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It may become necessary to recover or rebuild an LVM in case either a backup /etc/lvm/backup/<VOLGROUP> is not available or becomes lost or other conditions arise causing loss of system volume data.  What might otherwise appear destroyed, deleted or inaccessible, LVM comes with a few backup options in case of disaster.  Here are the recovery steps I took to recover previously lost data without either a backup and using only a few open source tools:

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In this upgrade, I planned to skip a version to see how things go jumping up two levels.  Unfortunately reading this post from The Register about Linus Torvalds had me thinking back to F14 again.  (This brings back fond memories of the KDE 4.0 desktop upgrade issues in F9 that didn't go so well.  I have a feeling I'll be going back to KDE but we'll find out soon enough) 

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Is this the smallest stop sign you've seen?

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