Chapter 13. CGL and LSB

In this chapter, you will be presented with information about the last topic of the book, the Carrier Grade Linux (CGL) and Linux Standard Base (LSB) initiative and of course, a parallel with what there is integrated and supported related to those two standards into the Yocto Project. This will also be mentioned here and you will not only be able to find a little bit about these standards and their specifications, but also about the level of support that Yocto offers for them. I will also present some of the initiatives adjacent to CGL, such as Automotive Grade Linux and Carrier Grade Virtualization. They also constitute viable solutions that are available in a wide palette of applications.

In any Linux environment today, there is necessity for a common language for available Linux distributions. This common language would have not been achieved without defining actual specifications. A part of these specifications is also represented by the carrier grade alternative...

Linux Standard Base

LSB appeared to lower the costs of support offered by Linux platforms by reducing the differences between various available Linux distributions. It also helps with costs for porting applications. Every time a developer writes an application, they need to make sure that the source code produced on one Linux distribution will also be able to be executed on other distributions as well. They would also like to make sure that this remains possible over the years.

The LSB workgroup is a Linux Foundation project that tries to address these exact problems. For this purpose, LSB workgroup started working on a standard that could describe a set of APIs that a Linux distribution should support. With the standards defined, the workgroup also moved a few steps further and developed a set of tools and tests to measure the support levels. With this done, they were able to define certain sets of compliance and also detect the certain differences between various distributions.

The LSB was...

Carrier grade options

Multiple options will be discussed in this section, and we'll start by defining the term carrier grade. This seems like the perfect start. So, what does this term mean in a telecommunications environment? It refers to a system, software, and even hardware components that are really reliable. Here, I am not referring only to the five-nines or six-nines that CGL provides because not all industries and scenarios require this kind of reliability. We are only going to refer to something that can be defined as reliable in the scope of a project. For a system, software, or hardware component to be defined as carrier grade, it should also prove itself as well tested along with all sorts of functionalities, such as high availability, fault tolerance, and so on.

These five-nines and six-nines refer to the fact that a product is available 99.999 or 99.9999 percent of the time. This translates per year in a downtime of around 5 minutes for five-nines and 30 seconds for six-nines...

Specific support for the Yocto Project

In the Poky reference system, support is provided for the development of LSB and LSB compatible applications. Inside Poky, there is a special poky-lsb.conf distribution policy configuration that is defined in case a distribution is interested in developing applications that are LSB-compliant. This holds true when generating a Linux distribution that is LSB-compliant or at least prepares to take the LSB certification. The build steps required for a Linux distribution that prepares for an LSB certification will be presented here. In case you are interested in developing LSB-compliant applications, the process is simpler and will also be briefly presented here; however, it is in contrast to the former.

The first step is simple: it only requires cloning the poky repository and the meta-qt3 dependency layer because of the requirements of the LSB modules:

git clone git://git.yoctoproject.org/poky.git
git clone git://git.yoctoproject.org/meta-qt3

Next, the...

Summary

In this chapter, you were presented with information about the specifications required for the Carrier Grade Linux and Linux Standard Base. Other options, such as Automotive Grade and Carrier Grade Virtualization, were also explained and in the end, support for the Yocto Project and a couple of demonstrations were shown to you to complete this learning process.

This is the last chapter of this book and I hope you've enjoyed the journey. Also, I hope I was able to pass on some of the information I have acquired on to you. Since we're at the end of this book, I must admit that I have also learned and gathered new information in the process of writing the book. I hope that you catch the Yocto bug as well and are also able to add your contributions to the Yocto Project and the open source community in general. I am confident that from now on, the embedded world holds fewer secrets for you. Make sure you shed some light about this topic on others too!