Roughly 1.5% of Workstations Run Linux and Linux vs. Windows at the Workplace

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Various companies such as Google use Linux desktops instead of Windows (according to ZDNet). According to TechReublic other big names that use it are NASA, the French military police, CERN (which is also known as the European Organization for Nuclear Research) and the U.S. Department of Defense. While an estimated 1.5% of desktops use Linux, it is a good choice for staying safe from viruses and spyware.

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How Do You Resume a DVD Movie Where You Stopped Watching It?

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Problem scenario
In Windows you sometimes watch DVDs but have to stop the movie mid-way through.  You cannot always watch an entire movie in one setting from start-to-finish.  You stop the DVD by closing Windows Media Player while the movie was still playing or paused.  Later after you have shut off your computer, you want to resume the DVD at the exact hour,

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How Do You Learn More About “Low Latency Programming”?

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Problem scenario
You want to learn more about low latency programming for working at a hedge fund company.  Where do you begin?

Solution
An Amazon search for “low latency programming” brings up books that could be very useful for other high-paying I.T. jobs in big data such as an Apache Thrift book or a book for Building a Columnar Database on RAMCloud. 

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How Do You Turn off OS Firewalls in an AWS Instance of Linux SUSE?

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Problem scenario
You are running Linux SUSE in AWS.  You want to have no firewalls running on the OS.  How can you be sure that there is no OS-level firewall running in Linux SUSE?

Solution
#1  Become root with this command: sudo su –
#2  Enter this command:  yast firewall
#3  You will see either a screen that warns you about another firewall running or you’ll see the YaST2 screen for a firewall. 

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How Do You Optimize SQL to Get Away from Disk Contention, to Reduce the I/O Activity?

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Problem scenario
Let’s say you want to rearrange the columns a of SQL table because a special order would make subsequent SQL commands easier.  Or you just want to avoid disk contention on the underlying storage device.  How do you optimize SQL to do less input/output activity on the disk while being able to rearrange the order of columns?

Solution
There are other ways such as avoiding “select *”,

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How Do You Troubleshoot the Hadoop NameNode Service Not Running Properly?

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Problem scenario
The Hadoop NameNode service won’t start.  You run start-dfs.sh and it starts the SecondaryNameNode and the DataNode.  It won’t start the NameNode.

Solution
Assumption: This solution only works if you are running the start-dfs.sh as a sudo user or the root user itself.

Procedures
Verify you can ssh with root to the localhost.  Run this command twice without exiting from the first session: 

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What Is an ARM in Modern Information Technology Vernacular?

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Question
What Is an ARM in Modern Information Technology Vernacular?

Answer / Disambiguation
In I.T. jargon the term ARM can refer to a number of different things.  Here are some potential definitions of this acronym in random order:

#1  Azure Resource Manager is a component of Azure.  It can be interacted with in the console if you log into a Azure via a web browser. 

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How Do You Create a Linux Server in Azure with PowerShell When You Keep Getting an Error “Status Code: 400…Bad Request”?

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Problem scenario
You are trying to create a Linux server in Azure with the Azure Tools for PowerShell.  You receive this message:

“Destination path for SSH public keys is currently limited to its default value due to a known issue in Linux provisioning agent.”

You see  “StatusCode: 400 … ReasonPhrase: Bad Request.”

What do you do to create an Ubuntu 16.x server and not get this error?

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How Do You Troubleshoot the Error “WARN conf.Configuration: bad conf file: element not < property >”?

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Problem scenario
You are trying to start HDFS.  But you get this error: “WARN conf.Configuration: bad conf file: element not <property>”

What should you do?

Solution
Look at mapred-site.xml, hdfs-site.xml, and core-site.xml files.  Verify you have a <property> tag in each file.

cat /path/to/mapred-site.xml | grep -i property
cat /path/to/hdfs-site.xml | grep -i property
cat /path/to/core-site.xml | grep -i property

If there is no <property>

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