Thursday, March 29, 2007

Passing the RHCT / RHCE Exams

Get Started

1) Take the Red Hat Training Courses (optional)
2) Study the objectives
https://www.redhat.com/training/rhce/examprep.html
3) Find some good reference materials
https://www.redhat.com/docs/manuals/enterprise/
4) Practice, practice, practice

How can you make a study guide?

Make some notes based on the objectives, labs, and potential questions.

1) Look at an objective
2) Ask yourself "what could they ask me to prove I know this objective?"
3) Write up as many potential questions, and answers as you can think of
4) Write down any supporting commands for configuring, testing or troubleshooting
5) Write down any files required for configuration
6) Test your theories, and try things out
7) Think about how you can test each of the changes you make to the system

Configuration Tips
Get a PC you can install and reinstall the OS on.
Learn what tools and files are used to configure a system.

OpenSource Software for Windows

Linux users are familiar with OpenSource, and the Free Software Foundation, but many Windows users still have no idea how much free software is available.

Sure freshmeat.net is always a good resource for sysadmins and power users, but beginners just want to know how to use their computer, and have no idea what software to use.

There are a few nice lists of software when searching Google for "open source software windows":
http://www.opensourcewindows.org
Top 10 open source Windows apps"
http://osswin.sourceforge.net
http://www.opensourcelist.org/oss/suggestedapplications.html
http://www.myopensource.org

And there are free CD's available for download from http://www.theopencd.org
and http://www.winlibre.com/en/Articles/Download/index_download.php

If you really want more, after searching freshmeat.net and sourceforge.net, check out the directory of software http://directory.fsf.org, which has over 5,000 entries so far. They are not listed by OS, but there are plenty of options.

"When we call software “free,” we mean that it respects the users' essential freedoms: the freedom to run it, to study and change it, and to redistribute copies with or without changes. This is a matter of freedom, not price, so think of “free speech,”, not “free beer.”" -- Richard Stallman

(http://www.gnu.org/philosophy/open-source-misses-the-point.html)

Here is another nice list that compares commercial software with free software.
http://linux.wordpress.com/2007/04/08/why-use-software-illegally-when-you-can-use-legally

Collection of stupid quotes made by clients during the Dot Com days.

This is a great thread from 2000, archived from the old Design Forum site, Dreamless.



read more | digg story

Wednesday, March 28, 2007

College Credit for IT Certifications

Did you know, you can receive undergraduate credit for IT Certifications? I was so happy to find out about this. I had taken off a few semesters from school to work on my certs. I had completed my CNE and was working on my MCSE, when I found out I could get credit for some of the exams. The coolest part was, that I didn't really lose any time by getting my certs. I was able to combine the best courses from some very good universities for a more well-rounded education.

Ways to Earn Credit
Earn undergraduate credit through Excelsior College courses and Excelsior College Exams, credit earned at other regionally accredited institutions, military training, corporate training, technology certification, and more. You may be closer than you think to earning your degree!

This looks like an add, but it is more of a personal endorsement. I highly recommend looking into this for any IT person who has not completed their degree yet. You have to keep up with certifications anyway, so why not get college credit for it?

You can receive credit for MCSE, CNE, CCNA, and other exams. Check out Excelsior College today!

read more | digg story

Free Screenshot Tips

Did you know...

that you can take a screen shot of the current window in Windows, or Linux (Gnome) by pressing Alt-PrintScrn? Use Alt-PrintScrn to take a shot of the current window. For the whole screen, try PrintScrn by itself.


Windows

In any version of Windows, since 95, pressing Alt-PrintScrn copies the current window to the clipboard. To get the image into something useful, you can open paint, and paste it in (ctrl-v). Then select any tool to de-select the "Select" tool, and then re-select it. Mark the area you want to keep, and cut it (ctrl-c) -- that puts the new selection on the clipboard. Now start a new file (save changes - no), shrink the box so your selection fills the box, and paste it in (ctrl-v).

Linux

Linux is not much different. In Gnome: Press Alt-PrintScrn, and a dialog box appears that prompts the user to save the image to a file.



If you have KDE installed you can use KSnapshot...

Tuesday, March 27, 2007

Searching for Software

An easy way to find free Open Source software is check out
http://freshmeat.net


Another place to look is
http://sourceforge.net

Unix / Linux Command Tips

When you're stuck, just remember "I'm a helpless man" Most commands allow the option "--help", which can then be redirected to "less" (or "more")
e.g.
cat --help | less

To see the man page (more detailed help) for a command type "man" followed by the command
e.g.
man cat

What if you don't remember the name of the command, but you know it was something like lvm? Try apropos

apropos lvm

What if the man page is the right name, but it displays something about c programming? Use the -a option, and press q until you get the the correct man page.

man -a cat

For more information look for a HOWTO or other documentation at the Linux Documentation Project -- http://www.tldp.org

Sunday, March 25, 2007

Topic-Specific Searches in Google

Did you know that you can perform topic-specific searches in Google?

e.g. to search for Linux specific topics, just enter
www.google.com/linux in the address bar of your
browser.


http://www.google.com/mac -- Apple Macintosh - Search for all things Mac
http://www.google.com/bsd -- BSD Unix - Search web pages about the BSD operating system
http://www.google.com/linux -- Linux - Search all penguin-friendly pages
http://www.google.com/microsoft -- Microsoft - Search Microsoft-related pages

For more information, go to google.com, and click on Advanced Search.

http://www.google.com/advanced_search?hl=en

The Screen Savers! - HDD switch

Switch between two Hard Drives without a boot loader, perfect for linux and windows!



TechTV
5 min 50 sec - Sep 1, 2004
link: thescreensavers.com

Friday, March 23, 2007

Network Config

How Do I Configure Networking in RedHat Linux?

Depending on the version of RedHat, or Fedora:

redhat-config-network
system-config-network

bash-2.05b$ which redhat-config-network
/usr/bin/redhat-config-network
bash-2.05b$

Network Related Files:

/etc/sysconfig/network-scripts/ifcfg-eth0
/etc/sysconfig/network
/etc/hosts
/etc/resolv.conf


For more details, remember that the Red Hat Manuals are available online:

http://www.redhat.com/docs/manuals

Network Info:
http://www.redhat.com/docs/manuals/enterprise/RHEL-4-Manual/ref-guide/s1-networkscripts-interfaces.html

Simple HD Config Question

> From: Brian
> Sent: Thursday, March 22, 2007 2:41 PM
> To: Scott
> Subject: Simple HD config Question
>
>
> When you have a desktop with a diagnostic partition on the hard drive (like HP or DELL) can > you keep the diagnostic partition or do you have to wipe it? If you do keep it do you have to > use a special boot loader to allow you to still access the partition?
>
>
>
> -Brian F.

--------------------------------------------------------------------------------

You don't really need it. The utilites are usually the same ones that are on the CD. Dell likes to make it easier for their support, since users lose CDs, and have no clue on how to download and burn another one.

Compaq had a requirement that the SmartStart CD be used in order to install NT, but that is no longer required.

If you run fdisk, and reformat the drive, you can reclaim the space.

- scottm

Captain's Log, Stardate date +%Y%m%d


How do you get the current date to use in a Linux / Unix shell script?

Take a look at this simple backup script:
----------------------------------------------------

#!/bin/sh

export FILE_DATE=`date +%Y%m%d`

export backup_file=backup_${FILE_DATE}.tgz

[ ! -d /opt/backups ] && mkdir -p /opt/backups

tar -zcvf /opt/backups/${backup_file} /var/named

----------------------------------------------------

What does that FILE_DATE variable do for me?

Well, let's try it on the command line.

bash-2.05b$ export FILE_DATE=`date +%Y%m%d`
bash-2.05b$ echo $FILE_DATE
20070323

Ah, so that's how we get the current date in a usable format. This method makes the files sortable later. Of course, if you need more than one backup per day, you can always add more date options.

Notice a few things about this method of scripting.

1) export, is optional, but it makes the environmet variable available to other scripts.
2) backticks ` are not to be confused with single quotes '
3) variables can be combined with text, or even become part of another variable. Not the ${} to enclose the variable name. The characters are optional when the variable is separated by spaces, but in this case, the variable is part of a string of text.

4) Note the common sysadmin trick of a one line if statement. Rather than using "if", we use the double ampersand "&&". This is interpreted as If the stuff in the brackets [ ] is true, then do the stuff on the right. So, basically, if there is no /opt/backups directory, then make one.

So what does the file look like when we run the script?

If you run it on March 23, 2007, it would look like this

/opt/backups/backup_20070323.tgz

In this example, we are just backing up /var/named, which is helpful for a DNS server, so you will have to modify as needed. The idea is just to show a few scripting techinques.


- scottm