Andrei Dumitru

Disable PC beep

If you installed or updated your laptop’s sound driver, you might hear an annoying beep sometimes(when plugging  your laptop charger, when using the function key Fn, etc. ). The beep is caused by the PC Speaker.
This is how you can disable it in Windows 7:

1. Go to Control Panel – Hardware and Sound – Sound
2. On the Playback tab choose your sound device (e.g. Speakers)
3. Click the Properties button
4. On the Levels tab mute the PC Beep or adjust the volume level.

Monitor Power Off

Q: What do you do if you go away from your computer for a while and want to turn off the screen to prolong its life time, save energy and reduce your carbon footprint ?
A: Use a software that can turn off your your monitor with just a mouse click.

Windows
On Windows NirCmd can be used. Just create a shorcut with the following target:

"C:\Program Files\nircmd\nircmd.exe" cmdwait 1000 monitor off

Linux
Create a script with the following commands.

#! /bin/sh
if [ ! -z $1 ] ; then
if [ -z "$(echo $1 | awk '/^[0-9]+$/')" ] ; then
echo Usage: poweroff_monitor [SECONDS]
echo Example: poweroff_monitor 10
echo If SECONDS is set, it waits SECONDS seconds before it suspends the monitor.
exit
fi
sleep $1
fi
xset dpms force standby

The  script can be used either as a shortcut from your favorite graphical interface or straight from the command line.

The Internet Revealed: A film about Internet Exchange Points

An Internet exchange point (IX or IXP) is a physical infrastructure through which Internet service providers (ISPs) exchange Internet traffic between their networks (autonomous systems). IXPs reduce the portion of an ISP’s traffic which must be delivered via their upstream transit providers, thereby reducing the average per-bit delivery cost of their service. Furthermore, the increased number of paths learned through the IXP improves routing efficiency and fault-tolerance. [Wikipedia]

via Cosu

How to install Java on RHEL 5

1. Check your operating system just to be sure:

[root@andrei ~]# cat /etc/redhat-release
Red Hat Enterprise Linux Server release 5.4 (Tikanga)

2. Check weather it’s a 32 or 64 bit version:

[root@andrei ~]# uname -a
Linux <output omitted> x86_64 x86_64 x86_64 GNU/Linux 


The current OS is a 64 bit system, indicated by  x86_64.

3. Download Java (JDK) – select Linux or Linux64 depending on your OS and download the required file. In my case is jdk-6u18-linux-x64-rpm.bin.

4. Make the downloaded file executable and then run it:

[root@andrei ~]# chmod u+x jdk-6u18-linux-x64-rpm.bin
[root@andrei ~]# ./jdk-6u18-linux-x64-rpm.bin

5. After you accept the License Agreement the installation starts.

6. Your Linux distribution most likely comes with a Java version installed, but it is probably the GNU Compiler for Java (gij – GNU libgcj).Now you need to configure the system to use the newly installed Sun Java.

[root@andrei ~]# alternatives --install /usr/bin/java java /usr/java/jdk1.6.0_18/bin/java 2
[root@andrei ~]# alternatives --config java

After the second command you will be asked to make a selection of the Java version used in your system. Choose option number 2.

7. Check that your system has a new Java environment:

[root@andrei ~]# alternatives --display java

See what version of Java Runtime Environment you are using now:

[root@andrei ~]# java -version
java version "1.6.0_18"
Java(TM) SE Runtime Environment (build 1.6.0_18-b07)
Java HotSpot(TM) 64-Bit Server VM (build 16.0-b13, mixed mode)

GNU/Linux Advanced Administration

The Free Technology Academy has released a book about “GNU/Linux Advanced Administration”. The book is divided in modules, each module being focused on a part of the Linux operating system. The main subject coverd by the book is system administration and you can download it from the FTA website.

From the FTA website:

The GNU/Linux systems have reached an important level of maturity, allowing to integrate them in almost any kind of work environment, from a desktop PC to the sever facilities of a big company.

Evolution of this book

The FTA has reused existing course materials from the Universitat Oberta de Catalunya (UOC). The first version of this course book was published in 2004 for the Master Programme in Free software of the UOC. In 2008, this book was translated into English with the help of the SELF (Science, Education and Learning in Freedom) Project, supported by the European Commission’s Sixth Framework Programme. In 2009, this material has been improved by the Free Technology Academy. Additionally the FTA has developed a study guide and learning activities which are available for learners enrolled in the FTA Campus.

The evolution of this books is interesting to me, because it has evolved from existing course materials. I think there are many books out there that have such an evolution and are designed with a specific goal in mind.

Freshmen who are attending the course “Operating Systems Usage” at the Computer Science Department of the “Politehnica” University of Bucharest have available a similar book written by the team in charge of the course. You can find it on Google books (Romanian version only).

[FTA via cibercity.biz]

iPad – Apple’s tablet

It’s out. iPad is its name and it’s Apple’s much awaited tablet. So, after all there is no iWish and no Duke Nuke Forever. Too bad.

You can view the list of features and tech specs  to see what’s above and under the hood.

iWish

Apple’s rumored tablet is making waves and some of them are funny. This is a good laugh and “iWish” it was true :).

[ from FEDO&PID’JIN ]

Remain active and up to date

I think the following resolution can be applied in most IT domains anytime.

Tom Kyte’s DBA Resolutions for 2009

Tom Kyte, Oracle DBA and founder of the Ask Tom blog, gave the Oracle Database Insider his resolutions for 2009 in hopes that other DBAs will follow suit. “In the coming year,” says Kyte, “I resolve to…

• Practice a restore at least once a month under different scenarios. DBAs are allowed to make mistakes—with one exception: They cannot make mistakes in recovery. We can fix any other mistake easily, but not recovery mistakes.
• Learn something new. When was the last time you read the “what’s new in” chapters in the documentation? Take a couple of minutes to see what’s new.
• Participate in user group discussion forums. If I just do the same thing day in, day out, never experiencing what others are doing, I’ll stagnate. The easiest way to stay current, to network, and to learn something new is to participate.
• Become a mentor for someone more junior. I’ll get two things out of this: First, I will learn a ton of new stuff because they will ask me things I don’t fully know. Second, I’ll have put in place the next generation of DBAs so that I can move up or move over in the future. Training your replacement is one sure way to be able to progress yourself.
• Be more thoughtful, don’t jump to conclusions, take my time. As the old saying goes, haste makes waste. And that is never more true than when doing something that will take hours or longer to accomplish, as many DBA tasks may take. I will study the options and pick the one that is best suited for the problem at hand—realizing that the approach I take in 2009 might be very different from the one I took in 2008, 2000, 1995, or any other time.

Source: Oracle Newsletter 2009

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