CSS Drop Down Menu Without Javascript

Aired Consulting 12/17/2014 No Comment

Lightweight and Pure CSS Drop Down Menu without Javascript

The menu is created in CSS3 which consists of a nested ul structure to create the second level of the menu. Just copy the below code below to give your website a beautiful, light-weight and flexible Drop down Menu.

HTML Code for CSS Drop Down Menu

<cssmenu>
<ul class="cf">
<li><a href="#">Menu 1</a></li>
<li><a class="dropdown" href="#">Menu 2</a>
<ul>
<li><a href="#">Sub Menu 1</a></li>
<li><a href="#">Sub Menu 2</a></li>
<li><a href="#">Sub Menu 3</a></li>
</ul>
</li>
<li><a href="#">Menu 3</a></li>
<li><a href="#">Menu 4</a></li>
</ul>
</cssmenu>

CSS Code for Drop Down Menu


cssmenu ul {
 text-shadow:0 1px 0 #FFF;
    background: #ddd;
    list-style: none;
    margin: 0;
    padding: 0;
    width: 100%;
}
cssmenu li {
    float: left;
    margin: 0;
    padding: 0;
    position: relative;
    min-width: 24.5%;
}
cssmenu a {
    background: #ddd;
    color: #444;
    display: block;
    font: bold 16px/50px sans-serif;
    padding: 0 25px;
    text-align: center;
    text-decoration: none;
    -webkit-transition: all .30s ease;
    -moz-transition: all .30s ease;
    -ms-transition: all .30s ease;
    -o-transition: all .30s ease;
    transition: all .30s ease;
}
cssmenu .dropdown:after {
    content: &#39; ▶&#39;;
}
cssmenu .dropdown:hover:after{
 content:&#39;\25bc&#39;
}
cssmenu li:hover a {
    background: #ccc;
}
cssmenu li ul {
    float: left;
    left: 0;
    opacity: 0;
    position: absolute;
    top: 35px;
    visibility: hidden;
    z-index: 1;
    -webkit-transition: all .30s ease;
    -moz-transition: all .30s ease;
    -ms-transition: all .30s ease;
    -o-transition: all .30s ease;
    transition: all .30s ease;
}

How to float DIV side by side using CSS

Aired Consulting 11/22/2014 No Comment

In this article, we will discuss how to place 3 DIV side by side using CSS.

You need to have a container with a width greater than the sum of the widths of the all the 3 DIV elements. For this purpose, we have kept width of the container element as 520px and the individual DIVs as 170px. Use the float as left, the DIVs will be arranged side by side.

If the page is to be expanded in the future, the sizes need to be re-adjusted. So, it is advisable to use percentage (%) instead of px for the DIVs.

<div style="width: 520px;">
<div style="float: left; width: 170px;">Left DIV</div>
<div style="float: left; width: 170px;">Middle DIV</div>
<div style="float: left; width: 170px;">Right DIV</div>
<br style="clear: left;" /></div>
</div>

How to disable Copy, Paste and Text Selection using CSS

Aired Consulting 4/04/2014 No Comment

Disable Copy/Paste and Text Selection using CSS and Javascript.

CSS Code to disable text selection and highlighting.

This CSS code will disable text highlighting and selecting for your website/blog post. This CSS code works perfectly in Internet Explorer, Mozilla Firefox and Google Chrome. In blogger you may put the code inside the .post-body section.
-webkit-user-select: none;
-khtml-user-drag: none;
-khtml-user-select: none;
-moz-user-select: none;
-moz-user-select: -moz-none;
-ms-user-select: none;
-o-user-select: none;
user-select: none;
One thing to note about the above CSS code is that in Firefox, it will also disable Copy/Paste of the content of your post/website. However, the copy will still be possible in Chrome browser.

CSS Code to enable text selection in Blockquote.

There may be cases where a certain portion of your post may still need the highlighting and selection, let say in the blockquote area where you may write certain sample code. In that case just you need to put
.post blockquote {
-webkit-touch-callout: text;
-khtml-user-select: text;
 -moz-user-select: text;
 -ms-user-select: text;
 user-select: text;
 -o-user-select:text;
 -webkit-user-select: text;
}

Disable Copy/Paste of you content.

To disable copy/paste in the blogger and Wordpress posts copy the below code into you theme template. This will make the task of copying text a little complex for content scrappers.
<script type='text/JavaScript'>
function killCopy(e){
return false
}
function reEnable(){
return true
}
document.onselectstart=new Function (&quot;return false&quot;)
if (window.sidebar){
document.onmousedown=killCopy
document.onclick=reEnable
}
</script>

Online HTML to XML Parser

Aired Consulting 3/04/2014 No Comment

HTML to XML Converter/Parser Tool. Convert your Blogger code from HTML to XML.

Convert your Adsense, Chitika or any other HTML code to XML and make it compatible with blogger templates.

Since Blogger doesn't allow HTML code, this tool will convert all the Javascript and HTML code to XML safely for use in Blogger.
Enter raw code here


Get escaped code here

HTML Table Generator

Aired Consulting 2/19/2014 1 Comment

Create a CSS styled HTML Table of your choice in real quick time.

This online tool will let you build and design your HTML table from a variety of styles. You just need to copy the HTML code generated into your website.

Please use the options provided below to create your custom HTML table.

Table Style: Highlight:

Table Structure: Columns Rows Cell Info:

Copy the HTML code generated below into your website

How HTML Table will look in your website or blog.

Header 1Header 2Header 3Header 4Header 5
Row:1 Cell:1Row:1 Cell:2Row:1 Cell:3Row:1 Cell:4Row:1 Cell:5
Row:2 Cell:1Row:2 Cell:2Row:2 Cell:3Row:2 Cell:4Row:2 Cell:5
Row:3 Cell:1Row:3 Cell:2Row:3 Cell:3Row:3 Cell:4Row:3 Cell:5
Row:4 Cell:1Row:4 Cell:2Row:4 Cell:3Row:4 Cell:4Row:4 Cell:5
Row:5 Cell:1Row:5 Cell:2Row:5 Cell:3Row:5 Cell:4Row:5 Cell:5
Row:6 Cell:1Row:6 Cell:2Row:6 Cell:3Row:6 Cell:4Row:6 Cell:5

CSS Code to make the footer stay at the bottom of a page

Aired Consulting 2/14/2014 No Comment

HTML page footer stay at bottom of the page.

CSS code for Footer at the bottom of a page.

Main body page is stretched to a 100% of the page. The footer is then given the below CSS rules
#footer {
clear: both;
position: relative;
z-index: 10;
text-align: center;
height:30px;
}

CSS code for Fixed Footer at the bottom.

There is another approach which will work on all browsers, though it will appear at the bottom, the footer will be placed over the content. As such, the footer will be at the bottom of the window even when you scroll.
#footer {
position:fixed;
bottom:0;
left:0;
right:0;
width:100%;
z-index: -999;
overflow: hidden;
}

Hadoop Cluster Interview Questions Answers

Aired Consulting 9/25/2013 No Comment

Apache Hadoop Cluster Interview Questions.

Explain about the Hadoop-core configuration files?
Hadoop core is specified by two resources. Its is configured by two well written xml files which are loaded from the classpath:
1. hadoop-default.xml  -  Read-only defaults for Hadoop, suitable for a single machine instance
2. hadoop-site.xml. - It specifies the site configuration for Hadoop distribution. The cluster specific information is also provided by the Hadoop administrator.

Explain in brief the three modes in which Hadoop can be run?
The three modes in which Hadoop can be run are:
1. Standalone (local) mode - No Hadoop daemons running, everything runs on a single Java Virtual machine.
2. Pseudo-distributed mode - Daemons run on the local machine, thereby simulating a cluster on a smaller sclae.
3. Fully distributed mode - Runs on a cluster of machines.

Explain what are the features of Stand alone (local) mode?

In stand-alone or local mode there are no Hadoop daemons running,  and everything runs on a single Java process. Hence we don't get the benefit of distributing the code across a cluster of machines. Since, it has no DFS, it utilizes the local file system. This mode is suitable only for running MapReduce programs by developers during various stages of development. Its the best environment for learning and good for debugging purposes.

What are the main features of Pseudo mode?

In Pseudo-distributed mode, each Hadoop daemon runs in a separate Java process, as such it simulates a cluster though on a small scale. This mode is used both for development and QA environments. Here , we need to do the configuration changes.

What are the features of Fully Distributed mode?

In Fully Distributed mode, the clusters range from a few nodes to 'n' number of nodes. It is used in the production environment, where we have thousands of  machines in the Hadoop cluster. The daemons of Hadoop run on these clusters.We have to configure separate masters and separate slaves in this distribution, the implementation of which is quite complex. In this configuration, Namenode and Datanode runs on different hosts and there are nodes on which task tracker runs. The root of the distribution is referred as HADOOP_HOME.

What are the Hadoop configuration files at present?
There are 3 configuration files in Hadoop:
1. conf/core-site.xml:
<configuration>     <property>         <name>fs.default.name</name>         <value>hdfs://localhost:9000</value>     </property></configuration>
2. conf/hdfs-site.xml:
<configuration>     <property>         <name>dfs.replication</name>         <value>1</value>     </property></configuration>

3. conf/mapred-site.xml:
<configuration>     <property>         <name>mapred.job.tracker</name>         <value>localhost:9001</value>     </property></configuration>
Does Hadoop follows the UNIX pattern?
Yes, Hadoop closely follows the UNIX pattern. Hadoop also has the ‘conf‘ directory as in the
case of UNIX.

In which directory Hadoop is installed?

Cloudera and Apache has the same directory structure. Hadoop is installed in cd
/usr/lib/hadoop-0.20/.

What are the port numbers of Namenode, job tracker and task tracker?

The port number for Namenode is ’70′, for job tracker is ’30′ and for task tracker is ’60′.

What is a spill factor with respect to the RAM?
Spill factor is the size after which your files move to the temp file. Hadoop-temp directory is
used for this.

Is fs.mapr.working.dir a single directory?

Yes, fs.mapr.working.dir it is just one directory.

Which are the three main hdfs-site.xml properties?

The three main hdfs-site.xml properties are:
1. dfs.name.dir which gives you the location on which metadata will be stored and where
DFS is located – on disk or onto the remote.
2. dfs.data.dir which gives you the location where the data is going to be stored.
3. fs.checkpoint.dir which is for secondary Namenode.

How to come out of the insert mode?

To come out of the insert mode, press ESC, type :q (if you have not written anything) OR
type :wq (if you have written anything in the file) and then press ENTER.

What is Cloudera and why it is used?

Cloudera is the distribution of Hadoop. It is a user created on VM by default. Cloudera
belongs to Apache and is used for data processing.

What happens if you get a ‘connection refused java exception’ when you type hadoop

fsck /?
It could mean that the Namenode is not working on your VM.

We are using Ubuntu operating system with Cloudera, but from where we can

download Hadoop or does it come by default with Ubuntu?
This is a default configuration of Hadoop that you have to download from Cloudera or from
Edureka’s dropbox and the run it on your systems. You can also proceed with your own
configuration but you need a Linux box, be it Ubuntu or Red hat. There are installation
steps present at the Cloudera location or in Edureka’s Drop box. You can go either ways.

What does ‘jps’ command do?

This command checks whether your Namenode, datanode, task tracker, job tracker, etc are
working or not.

How can I restart Namenode?

1. Click on stop-all.sh and then click on start-all.sh OR
2. Write sudo hdfs (press enter), su-hdfs (press enter), /etc/init.d/ha (press enter) and
then /etc/init.d/hadoop-0.20-namenode start (press enter).

What is the full form of fsck?

Full form of fsck is File System Check.

How can we check whether Namenode is working or not?

To check whether Namenode is working or not, use the command /etc/init.d/hadoop-
0.20-namenode status or as simple as jps.

What does the command mapred.job.tracker do?

The command mapred.job.tracker lists out which of your nodes is acting as a job tracker.

What does /etc /init.d do?

/etc /init.d specifies where daemons (services) are placed or to see the status of these
daemons. It is very LINUX specific, and nothing to do with Hadoop.

How can we look for the Namenode in the browser?

If you have to look for Namenode in the browser, you don’t have to give localhost:8021, the
port number to look for Namenode in the brower is 50070.

How to change from SU to Cloudera?

To change from SU to Cloudera just type exit.

Which files are used by the startup and shutdown commands?

Slaves and Masters are used by the startup and the shutdown commands.

What do slaves consist of?

Slaves consist of a list of hosts, one per line, that host datanode and task tracker servers.

What do masters consist of?

Masters contain a list of hosts, one per line, that are to host secondary namenode servers.

What does hadoop-env.sh do?

hadoop-env.sh provides the environment for Hadoop to run. JAVA_HOME is set over here.

Can we have multiple entries in the master files?

Yes, we can have multiple entries in the Master files.

Where is hadoop-env.sh file present?

hadoop-env.sh file is present in the conf location.

In Hadoop_PID_DIR, what does PID stands for?

PID stands for ‘Process ID’.

What does /var/hadoop/pids do?

It stores the PID.

What does hadoop-metrics.properties file do?

hadoop-metrics.properties is used for ‘Reporting‘ purposes. It controls the reporting for
Hadoop. The default status is ‘not to report‘.

What are the network requirements for Hadoop?

The Hadoop core uses Shell (SSH) to launch the server processes on the slave nodes. It
requires password-less SSH connection between the master and all the slaves and the
secondary machines.

Why do we need a password-less SSH in Fully Distributed environment?

We need a password-less SSH in a Fully-Distributed environment because when the cluster
is LIVE and running in Fully
Distributed environment, the communication is too frequent. The job tracker should be
able to send a task to task tracker quickly.

Does this lead to security issues?

No, not at all. Hadoop cluster is an isolated cluster. And generally it has nothing to do with
an internet. It has a different kind of a configuration. We needn’t worry about that kind of a
security breach, for instance, someone hacking through the internet, and so on. Hadoop has
a very secured way to connect to other machines to fetch and to process data.

On which port does SSH work?

SSH works on Port No. 22, though it can be configured. 22 is the default Port number.

Can you tell us more about SSH?

SSH is nothing but a secure shell communication, it is a kind of a protocol that works on a
Port No. 22, and when you do an SSH, what you really require is a password.

Why password is needed in SSH localhost?

Password is required in SSH for security and in a situation where passwordless
communication is not set.

Do we need to give a password, even if the key is added in SSH?

Yes, password is still required even if the key is added in SSH.

What if a Namenode has no data?

If a Namenode has no data it is not a Namenode. Practically, Namenode will have some
data.

What happens to job tracker when Namenode is down?

When Namenode is down, your cluster is OFF, this is because Namenode is the single point
of failure in HDFS.

What happens to a Namenode, when job tracker is down?

When a job tracker is down, it will not be functional but Namenode will be present. So,
cluster is accessible if Namenode is working, even if the job tracker is not working.

Can you give us some more details about SSH communication between Masters and

the Slaves?
SSH is a password-less secure communication where data packets are sent across the slave.
It has some format into which data is sent across. SSH is not only between masters and
slaves but also between two hosts.

What is formatting of the DFS?

Just like we do for Windows, DFS is formatted for proper structuring. It is not usually done
as it formats the Namenode too.

Does the HDFS client decide the input split or Namenode?

No, the Client does not decide. It is already specified in one of the configurations through
which input split is already configured.

In Cloudera there is already a cluster, but if I want to form a cluster on Ubuntu can

we do it?
Yes, you can go ahead with this! There are installation steps for creating a new cluster. You
can uninstall your present cluster and install the new cluster.

Can we create a Hadoop cluster from scratch?

Yes we can do that also once we are familiar with the Hadoop environment.

Can we use Windows for Hadoop?

Actually, Red Hat Linux or Ubuntu are the best Operating Systems for Hadoop. Windows is
not used frequently for installing Hadoop as there are many support problems attached
with Windows. Thus, Windows is not a preferred environment for Hadoop.

Big Data Resources - Interview Questions, Downloads, Tutorials

Aired Consulting 9/22/2013 No Comment

Big Data Interview Questions, Downloads, Tutorials.

Apache Hadoop Interview Questions Answers

MapReduce Interview Questions

Apache Pig Interview Questions Answers

Big Data Downloads 

 

 

Aired | Copyright © 2009-2014| All Rights Reserved 2014 | Privacy Policy and Disclaimer

Contact Us | About Us