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Red Hat Courts Antsy Unix Users with RHEV 3.6 Release

With the release of Red Hat Enterprise Virtualization 3.6, Red Hat has set its sites on helping to move mission critical Unix workloads over to Linux machines.

“We have continued to see demand for mission-critical workloads that have previously avoided virtualization, especially those tied to Unix-to-Linux migrations,” wrote Scott Herold, Red Hat principal product manager for RHEV, in an email. “RHEV 3.6 ties these mission-critical workloads directly to Unix-Linux migrations with new storage throughput features.”

The release comes with a number of other new features as well, including add management consoles and tooling capabilities and tighter integration with Red Hat CloudForms, the company’s hybrid cloud management software. 

Coffee Shop DevOps: Start Small, But Start Somewhere

coffee-shop-devopsI was recently talking to an engineer friend of mine over of a cup of coffee at a conference. His company had been in “DevOps strategy planning” for over six months and they had settled on the task of automating the delivery of their software. He was feeling frustrated—there never seemed to be enough time to get anything meaningful done, he couldn’t tell what others were doing, and a recent conversation revealed that not everyone had the same definition for “automating the delivery of software”, much less having the same ideas behind what the word DevOps meant.

…In this column, Coffee Shop DevOps, over the next 12 months, I’ll touch on some of the key things you and your organization can do to make incremental progress without taking on big hairy audacious goals

Read more at OpenSource.com

Linux 4.6 Will Improve the Security of 32-bit Programs

Besides the 4.6 scheduler updates, another interesting pull request today by Ingo Molnar are the mm updates. 

Most notable to the mm pull request is the enabling of full ASLR randomization for 32-bit programs. Yes, about Address Space Layout Randomization. If you’re not familiar with it, see Wikipedia

The enabling of full randomization on i386 and x86_32 was done by Hector Marco-Gisbert. He explained in the patch: 

Read more at Phoronix

Mesos Will Support Multiple Container Formats with Unified Containerizer

Apache Mesos has been supporting Docker as an alternate to its own default container since late 2014. But now the popular open source cluster scheduler platform  is nearing completion on a more simplified approach that intends to replace both of the two existing containers in the hopes of easing future development of frameworks.

In addition to this goal, this new “unified containerizer†will allow newer container formats to be much more easily added into Mesos. Projects like rkt, appc and any future workout of the Open Container Initiative are alternatives to the more well-known Docker format that will likely become more prevalent over time as each finds their niche use case.

Read more at The New Stack

KVM Changes Ready for the Linux 4.6 Kernel

Paolo Bonzini has sent in the KVM (Kernel-based Virtual Machine) changes for the Linux 4.6 kernel merge window, which he describes as “one of the largest releases for KVM.” 

While the KVM changes for Linux 4.6 are numerous, they are mostly architecture-specific changes for this important piece of the open-source Linux virtualization puzzle. 

Read more at Phoronix

Absolute Path vs Relative Path in Linux/Unix

One of this blog follower asked us that whatâs the difference between absolute and relative path?

To understand this we have to know what is a path in Linux.

What is a path?

A path is a unique location to a file or a folder in a file system of an OS. A path to a file is a combination of / and alpha-numeric characters.

What is an absolute path?

An absolute path is defined as the specifying the location of a file or directory from the root directory(/). In other words we can say absolute path is a complete path from start of actual filesystem from / directory.

Some examples of absolute path:

/var/ftp/pub
/etc/samba.smb.conf
/boot/grub/grub.conf

If you see all these paths started from / directory which is a root directory for every Linux/Unix machines.

What is the relative path?

 

Relative path is defined as path related to the present working directory(pwd). Suppose I am located in /var/log and I want to change directory to /var/log/kernel. I can use relative path concept to change directory to kernel

 

changing directory to /var/log/kernel by using relative path concept.

 

pwd/var/logcd kernel

 

Note: If you observe there is no / before kernel which indicates itâs a relative directory to present working directory.

 

Changing directory to /var/log/kernel using absolute path concept.

 

cd /var/log/kernel

 

Note: We can use an absolute path from any location where as if you want to use relative path we should be present in a directory where we are going to specify relative to that present working directory.

 

Examples of relative path and absolute path for the same operation.

Read full post:  http://www.linuxnix.com/abslute-path-vs-relative-path-in-linuxunix/

 

Is Infinite Scrolling Right for Your Website

infinite scrolling

If you have used (and of course you have) Pinterest, Facebook or Twitter or have searched Google images, you have already seen infinite scrolling in action. Just keep scrolling down and the never-ending list keeps popping up more and more information. Apart from Pinterest, Twitter, and Google images, infinite scrolling is being used by many small business blogs as well as leading news websites. Inc. Magazine, Mashable and The Chicago Tribune etc. are great examples of news sources using infinite scrolling. The next time you visit these websites, just notice how you can scroll down to enjoy the continuous flow of information.

Infinite scrolling is one of the trending ways to display content, which marketers are largely using to improve their website’s user experience. But from the design perspective, is it the right thing for your website?

To Scroll or Not to Scroll

Infinite scrolling is basically long lists, which are nothing new. What has changed now is the way we are scrolling these long lists, especially after the introduction of mobile interfaces and the popularity of mobile app development. Since the mobile screens are typically narrow, it is essential to arrange list items vertically. As a result, we need to scroll them frequently to view the content. The basic functionality of infinite scrolling is simple. As users scroll through the content and images, it automatically loads more content.

But before zeroing on infinite scrolling, designers and developers need to consider the type of website they are working on.

Use infinite scrolling if you have image-heavy content. Also, if you think your visitors aren’t looking for something specific. You need to understand the user intent to be successful with your infinite page. Etsy, for example, experienced horrible results with infinite scrolling and ended-up with a low CTR. Why? Simply because it distracted the users and as a result, they are likely to click less items that than they would normally do. It’s just not Esty, any other eCommerce sites would have faced a similar situation.

Another situation where a designer might like to consider using infinite scrolling is on websites that have a lot of user-generated, low-engagement content. People usually scroll down the list on these websites without actively interacting with it all the time. Facebook and Twitter are the best examples. While we are at it, it is important to consider that websites with interactive and high-engagement content, which is meant to hold the readers’ interest for a long period of time aren’t good candidate for infinite scrolling.

Designers and developers also tend to use infinity scrolling for websites that cannot control the variables in their content type. These websites has both high and low user engagement content. Tumblr is perhaps the best example, which uses infinite scrolling to reduce users’ options of interacting with individual post. As a result, the high engagement users can better focus on individual posts, while low engagement users can continue browsing more content. What Tumblr does differently is that it allows users to enable or disable infinite scrolling, giving them total control over how they want to interact with the content.

Today’s web designers are largely using a hybrid approach to their scrolling solutions, by which they prompt users to load additional content after they reach the end of a webpage. This is a smart approach where users again have the control over how much content they want to consume and this works best on mobile.

The secret is to tread carefully with infinite scrolling. Despite that, things can go wrong. We are not just talking about how things went wrong with Etsy, which made an erroneous decision of switching to infinite scroll a few years back. We now know that this technique works best with social media, entertainment and news sources and is a total disaster for ecommerce websites. But there’re are other problems too and some of them are related to SEO – one thing designers and developers often overlook.  

SEO Issues with Infinite Scrolling and How You Can Fix Them

Infinite scrolling incorporates JavaScript, which is the source of all SEO issues associated with this technique. Google and other major search engines do not crawl most JavaScript successfully. Google too a few suggestions for webmasters and designers when using fancy features like JavaScript. The best practice is to put your content in basic HTML so that search engines can easily crawl and index the pages. However, content loaded via JavaScript is less likely to be indexed as crawlers don’t keep scrolling like humans to consume content.

That being said, there are some ways to create searchable infinite scroll pages.

According to Google, you need to create a series of other pages (paginated series or component pages) to go along with your infinite scroll page. This allows you to chunk your infinite scroll page into component pages.

Here are a few tips to do it:

1. Divide Your Content to Avoid Overlapping

Determine the amount of content you want to include on each page and break it up into chunks in such a way that your users can easily find the information they are looking for. These compound pages should not have duplicate content and also ensure they have optimal load times.

2. Your URL Structure Must Accommodate Infinite Scrolling

You will need a URL structure for your infinite scroll pages, maintaining the sequential nature. Each section of your infinite scroll content is a unique page and needs a unique URL. Google recommends using full URLs to reduce configuration errors.

The following URL patterns are acceptable as per Google:

  • example.com/category?name=fun-items&page=1
  • example.com/fun-items?lastid=567
  • example.com/fun-items#1 (although this one is less optimal)

Google also advice to avoid two things:

  • No relative-time-based URL parameters as it adversely affect SEO
  • No code-based language to ensure an enhanced user experience

3. Don’t Forget Your Pagination Codes

Each component page must include rel=next and rel=prev values within the <head> tag. This is to ensure that Googlebot crawls, indexes and returns these component pages sequentially. Besides, Google simply ignores such pagination codes in the <body> for indexing purposes.

4. Implement PushState

An HTML5 method, PushState dictates the load process, telling the browser what to load and/or display. Twitter uses PushState to implements its infinite scroll. Implement this in conjunction with ReplaceState to allow users to serially backup their most recently paginated content. It also helps you to respond to your users’ scrolling behavior.

Conclusion

If you think infinite scrolling will add to your benefits, definitely go for it. But make sure your codes are SEO-friendly and also implement SEO best practices on each page to make your infinite scroll pages searchable. Remember infinite scrolling is after all just a design option. The ultimate goal is not about trying something new, it’s about providing the best possible experience to your visitors.

Author Bio:-

Jaykishan Panchal is a content marketer at MoveoApps, an iphone app development company. He enjoys writing about Technology, marketing & industry trends. He is tech enthusiast and love to explore new stuff. You can follow him on Twitter @jaypanchal8.

Watch Open Networking Summit This Week via Free Live Video Stream

ONS speakers

Open Networking Summit (ONS) takes place this week, March 14-17, in Santa Clara, Calif., with talks covering every aspect of open networking for developers, technologists, operators, service providers and executives.

You can watch the keynotes and plenary sessions live on free, streaming video (email registration required), starting on Tuesday, March 15, at 8:30 a.m. PST.

ONS has become a recognized forum for major industry announcements and the introduction of open source networking projects. AT&T, Google and The Linux Foundation, among others have announced major networking projects and initiatives at ONS over just the last few years.

Stay tuned again this year for new project announcements and industry-wide updates from service providers, vendors and open source SDN/NFV projects including:

  • Jigar Desai, Vice President, Cloud and Platforms, PayPal

  • John Donovan, Senior Executive Vice President of AT&T Technology and Operations

  • Travis Evert, SVP Global Network Software Development, Level 3 Communications

  • Neela Jacques, Executive Director, OpenDaylight

  • Heather Kirksey, Executive Director, OPNFV

  • Peter Levine, Partner, Andreessen Horowitz

  • Ayush Sharma, Senior Vice President, CTO-Networks Business Unit, Huawei

  • David Ward, Senior Vice President, Chief Architect, & CTO – Engineering, Cisco Systems

 

Numerous technical talks will also be held, and video recordings of these sessions will be available on Linux.com following the event.

View the entire schedule of 100+ conference sessions.

Linux:Copy, change permissions and ownership of a file in a command

Today I came across a requirement to copy couple of files and change permissions to execute those files when writing some ansible playbooks. We can do this by using cp, chmodchowncommand as shown below. Ownership is changed from root user to normal user surendra.

ls -l abc.sh

output:

-rw-r–r– 1 root root 0 Jun 10 21:22 abc.sh

cp abc.sh /tmp/
chmod 755 /tmp/abc.sh
chown surendra.surendra /tmp/abc.sh

ls -l /tmp/abc.sh

Output:
-rwxr-xr-x 1 surendra surendra 0 Jun 10 21:23 /tmp/abc.sh

I can execute these commands with out any problem, but if you want to do same activity on a regular basis then it is time consuming task and more over keeping these commands in ansible play-book is not a great option. How about if we have a command in Linux which do all these stuff in one shot? Yes, we have a command called “install” which do this all in one command. The equivalent install command of above three commands is below.

install -v -g surendra -o surendra -m a+x abc.sh /tmp/abc.sh

To understand above command we should know couple of options for install command. Below examples will help you to understand install command with ease.

Example: Just copy a file from one location to other and do not bother about permissions and ownership.

install abc.sh /tmp

Example: Copy a file with different permissions, for example every user in my machine should have execute permission on the file

install -m a+x abc.sh /tmp/

Note: -m option arguments will be similar to chmod arguments.

Example: Copy a file with different permissions, for example full permissions for a file for all the users.

install -m 777 abc.sh /tmp/

Example: Copy a file with different owner name

install -m 755 -o surendra abc.sh /tmp/

Example: Copy a file with different group owner

read full post: http://www.linuxnix.com/linuxcopy-change-permissions-and-ownership-of-a-file-in-a-command/

 

How To Install a Mumble Server on CentOS 7

Mumble is a free application primarily intended for use by gamers which allows users to talk to each other while gaming. In this article, I will show you how to install the Voice Over IP application Murmur on CentOS 7.

Read more at HowtoForge