We’re learning about Kubernetes in this series, and why it is a good choice for managing your containerized applications. In part 1, we talked about what Kubernetes does, and its architecture. Now we’ll compare Kubernetes to competing container managers.
One Key Piece of the Puzzle
As we discussed in part 1, managing containers at scale and building a distributed applications infrastructure requires building a large complex infrastructure. You need a continuous integration pipeline and a cluster of physical servers. You need automated systems management for testing and verifying container images, launching and managing containers, performing rolling updates and rollbacks, network self-discovery, and mechanisms to manage persistent services in an ephemeral environment.
Kubernetes manages several important tasks.
Kubernetes is just one piece of this puzzle. But it is a very important piece that manages several important tasks (Figure 1). It tracks the state of the cluster, creates and manages networking rules, controls which nodes your containers run in, and monitors the containers. It is an API server, scheduler, and a controller. That is why it is called “Production-Grade Container Orchestration,” because Kubernetes is like the conductor of a manic orchestra, with a large cast of players that constantly come and go.
Other Solutions
Kubernetes is a mature and feature-rich solution for managing containerized applications. It is not the only container orchestrator, and there are four others that you might be familiar with.
Docker Swarm is the Docker Inc. solution, based on SwarmKit and embedded with the Docker Engine.
Apache Mesos is a datacenter scheduler, which runs containers through the use of frameworks such as Marathon.
Nomad from HashiCorp, the makers of Vagrant and Consul, schedules tasks defined in Jobs. It includes a Docker driver for defining a running container as a task.
Rancher is a container orchestrator-agnostic system that provides a single interface for managing applications. It supports Mesos, Swarm, Kubernetes, and its native system, Cattle.
Similarities with Mesos
At a high level, there is nothing different between Kubernetes and other clustering systems. A central manager exposes an API, a scheduler places the workloads on a set of nodes, and the state of the cluster is stored in a persistent layer.
For example, you could compare Kubernetes with Mesos, and you would see a lot of similarities. In Kubernetes, however, the persistence layer is implemented with etcd instead of Zookeeper for Mesos.
You could also consider systems like OpenStack and CloudStack. Think about what runs on their head node, and what runs on their worker nodes. How do they keep state? How do they handle networking? If you are familiar with those systems, Kubernetes will not seem that different. What really sets Kubernetes apart is its fault-tolerance, self-discovery, and scaling, and it is purely API-driven.
In our next blog, we’ll learn how Google’s Borg inspired the modern datacenter, and Kubernete’s beginnings as Google Borg.
Networking has always been one of the most persistent headaches when working with containers. Even Kubernetes—fast becoming the technology of choice for container orchestration—has limitations in how it implements networking. Tricky stuff like network security is, well, even trickier.
Now an open source project named Cilium, which is partly sponsored by Google, is attempting to provide a new networking methodology for containers based on technology used in the Linux kernel. Its goal is to give containers better network security and a simpler model for networking.
The computer systems we use today make it easy for programmers to mitigate event latencies in the nanosecond and millisecond time scales (such as DRAM accesses at tens or hundreds of nanoseconds and disk I/Os at a few milliseconds) but significantly lack support for microsecond (μs)-scale events. This oversight is quickly becoming a serious problem for programming warehouse-scale computers, where efficient handling of microsecond-scale events is becoming paramount for a new breed of low-latency I/O devices ranging from datacenter networking to emerging memories (see the first sidebar “Is the Microsecond Getting Enough Respect?”).
Certifications are important for you to showcase tech skillsto your employer. The IT certifications are in high demand due to advancement on technologies like cloud computing, Big Data, etc. There are companies where being certified gives you an edge over other candidates. And in some cases, you may be offered a slightly higher pay.
PL/SQL Developer
SQL is used across all databases and is useful and necessary in every project that needs to store data (i.e. 99% of all). PL/SQL is a specialty programming language used for coding inside the Oracle database. It fills that role supremely well, but its skills are only useful for a small subset of tasks (database logic) and only with a few organizations (large organizations who need and can afford expensive Oracle databases). The daily responsibilities of an SQL or PL/SQL developer may include writing codes, queries and function in order to manipulate the data and structure of a database using the Structured Query Language.
Following are the advantages of ORACLE Certified PL/SQL Developer:
You will get better pay, billing
You will get better identity in the market
You can get more opportunities if interested to work as a freelancer.
Some Customers/Clients prefer certified candidates for their project works.
An SQL developer may also be responsible for querying a database to generate reports or aggregate data for use by others. PL/SQL developers work particularly with Oracle database. These SQL developers may work with Microsoft SQL Server, MySQL or one of many other database systems. Tech Skills must include knowledge of SQL programming, strong logical and analytical ability.
Cloud/SaaS
Cloud computing is poised to change the way people do business and communicate over the Internet. It is considered to be the upcoming big revolution in the IT industry. So, it goes without mention that if you are a certified and trained cloud computing professional, you would be in great demand. You would also get to learn a lot. Here’s a list of the top cloud computing certification and training companies across the globe.
Cloud Administrator Certifications — Top-notch credentials oriented to the everyday operations, troubleshooting and configuration of cloud technologies.
Cloud Developer Certifications — A handful of credentials of specific value to IT experts seeking to ply their trade in the cloud.
Cloud Architect Certifications — This certification is best for those of you with design skills and goals, whether for developing enterprise-level private clouds from the infrastructure or developing cloud storage solutions.
The certifications on these lists cover private and public cloud technologies, a broad expanse that includes :
SaaS – Software as a Service
PaaS – Platform as a Service
IaaS – Infrastructure as a Service
Oracle Enterprise Resource Planning Cloud
The Certificate in Enterprise Resource Planning (ERP) with Oracle will instruct you in Oracle Enterprise Resource Planning software, an integrated multi-module application that supports business forms. Oracle is one of the top ERP vendors and the skills gained will allow you to become more valuable in the current commercial place. Oracle certification is valuable to hire managers who want to distinguish among certified candidates for critical IT experts position.
This program enables students to become skilled in Oracle Supply Chain and sets them up for the Oracle Supply Chain Certified Professional Consultant examination. Students who complete this certification will have the ability to implement and support eBusiness Supply Chain applications.
Web development
Java is a widely used computer programming language. Web developers use it to create applications found across the Internet via multiple platforms, for example PCs and smartphones. Web developers design and create websites, maintain client websites, troubleshoot problems, and write code for Java-enabled websites. Oracle has certifications divided into two different levels.
Oracle Certified Associate (OCA) is the entry level exam in the Oracle certification path. This OCA exam tests the fundamentals and basics of the technology. For candidates that have achieved this certification without any work experience, the expectation is that they have show knowledge of the fundamentals and can be expected to perform satisfactorily under supervision.
Oracle Certified Professional (OCP) is the second level in the Oracle certification way. This examination tests your in-depth knowledge on the technology. Bu, still it is not the final level. There are Oracle Certified Master (OCM)and Oracle Certified Expert (OCE) as the more advanced level of Oracle certifications.
Big Data
The field of big data, analytics and business intelligence is extremely popular, and the number of certifications is ticking up accordingly. Furthermore, IT experts with big data and related certifications are growing in demand. Big data system administrators manage, store and transfer large sets of data, making it accessible for analysis. Data analytics is the practice of examining the raw data to draw conclusions and recognize patterns.
Koenig Solutions has innovative solutions for the training market. It teaches all the above subjects in great detail and makes students ready for the industry.
Docker, microservices, Continuous Delivery are currently some of the most popular topics in the world of programming. In an environment consisting of dozens of microservices communicating with each other, it seems to be particularly important the automation of the testing, building, and deployment process. Docker is an excellent solution for microservices because it can create and run isolated containers with service.
Today, I’m going to present you how to create a basic Continuous Delivery pipeline for sample microservices using a popular software automation tool: Jenkins.
“Container orchestrators need community-driven container runtimes,” reads a formal statement from CNCF Executive Director Dan Kohn Wednesday, “and we are excited to have containerd which is used today by everyone running Docker. Becoming a part of CNCF unlocks new opportunities for broader collaboration within the ecosystem.”
This week in open source and Linux news, Cloud Foundry releases its new certification program for developers, Google creates a new home-base for its open source initiatives, and more! Read on to stay in the open source loop!
1) Cloud Foundry launches “the world’s largest cloud-native developer certification initiative.”
3) Hyperledger Executive Director Brian Behlendorf talks about the “possibilities blockchain offers for transparent, efficient and quickly executed transactions” in this interview.
Most modern Linux distributions enjoy standard repositories that include most of the software you’ll need to successfully run your Linux server or desktop. Should a package come up missing, more than likely you’ll find a repository you can add, so that the installation can be managed with the built-in package manager. This should be considered a best practice. Why? Because it’s important for the integrity of the platform to ensure the package manager is aware of installed software. When that is the case, packages can easily be updated (to fix vulnerabilities and the like). Another reason to install from repositories is that dependencies are easily met. When installing from source, you can sometimes find yourself trapped in a convoluted dependency nightmare.
Fortunately, repositories have become so inclusive, that it is rare you will ever need to install a package by any other means. However, you may find, on occasion, a reason to install from source. Reasons could include:
A package that is not found in any repository
A package developed in-house
You need to install a package with custom dependencies or options
When you do have to install from source, there are certain things you will need to know. Let’s walk through the process of installing Audacity from source on Ubuntu 16.10 (with the help of build-dep). Although this can be easily installed from repositories, it serves as a fine illustration for installing from source.
First things first
Installing from source used to be very common and also quite simple. You would download the source file, unpack it (with either zip or tar), change into the newly created directory, and then issue the commands:
./configuremakemake install
That still works for applications built with autoconf/automake. As long as your distribution met the necessary dependencies (which were almost always outlined in a README file within the source), the package would install and could be used. Although some source installations are still that simple, things are now a bit more complicated.
Another glitch in the modern system is that Ubuntu doesn’t ship with all the necessary tools to build from source. To solve that issue, you must first install autoconf with the command:
sudo apt-get install autoconf
Depending upon which version of Ubuntu you installed, you may even have to install the build-essential and build-dep packages (which includes the gcc/g++ compilers and libraries as well as a few other necessary utilities). These two packages can be installed with the command:
sudo apt-get install build-essential build-dep
For the likes of Fedora, a similar installation would be:
sudo yum install yum-utils
The above command would install the yum-builddep package.
Installing from source with build-dep
One way to install from source, but avoid the dependency nightmare, is to first work with the build-dep tool. Say you want to install audacity using build-dep; the first thing you must do is uncomment the deb-src listings in /etc/apt/sources.list. Open that file in your favorite editor and then uncomment out the two deb-src listings, by removing the leading # characters (Figure 1).
Figure 1: Configuring apt so it can use build-dep.
Save and close that file. Now run sudo apt-get update to update apt. Once that is done, you’re ready to build Audacity from source. Here’s what you must do. The first step is to use apt to install the necessary dependencies for Audacity. This is taken care of with the command:
sudo apt-get build-dep audacity
Allow that command to finish. The next step is to download the source package with the command:
sudo apt-get source audacity
In your current working directory, you should see a new directory called audacity-XXX (where XXX is the release number). Change into that directory. At this point, you can now issue the old tried and true:
./configuremakesudo make install
Audacity should now be installed and ready to use.
If the installation fails, you might have to revert to using the dpkg tool like so:
sudo dpkg-buildpackage -b -uc -us
The options above are as follows:
b – build binary
uc – do not sign the .changes file
us – do not sign the source package
Why might a source package fail to install? Beyond not having all of the necessary dependencies, the answer very well might lie in the ./configurecommand.
The magic of configure
That configurecommand does have some magic hidden within. Most often you can run the ./configure command without any arguments. However, there are times you might want (or be required) to issue the command such that it configures the software to meet certain needs. Fortunately, themake tool can help us here. If you issue the command ./configure –help (from within the application source directory you’ve downloaded), you will be presented with a list of configuration options that can be used (Figure 2), specific to that package.
Figure 2: Options available for the source installation of Audacity.
These options can sometimes mean the difference between an application installing or not. Every application you attempt to install will display different options for the ./configure command, so make sure to issue ./configure –help before issuing./config. Possible configuration options include:
–prefix=PREFIX(install architecture-independent files in a non-standard location such as –prefix=/opt)
–build=BUILD (configure for a specific system architecture)
–host=HOST (the architecture of the system you want the file to run on, so you can compile the application on one machine and run it on another)
–disable-FEATURE (this allows you to disable specific features of an application)
–enable-FEATURE (this allows you to enable specific features of an application)
–with-PACKAGE=yes (use a specific PACKAGE)
–without-PACKAGE (do not use a specific PACKAGE)
As I mentioned, every software to be installed will offer different configuration options. Once you’ve decided on your options, you would then run the ./configurecommand (with all options). Once the configure script completes, follow it up with make and then make install to complete the installation.
Using Git
Let’s walk through another example, this time with the help of Git. As Ubuntu doesn’t ship with Git installed, we’ll first have to install it with the command:
sudo apt-get install git
Once this is installed, let’s pull down the source for the Clementine audio player with the command:
With the source downloaded, change into the newly added directory with the command cd Clementine. At this point, run the following commands to build the player from source:
cd bincmake ..make -j8sudo make install
That’s it. You should now have a working install of Clementine (so long as you’ve met the necessary dependencies). If the installation complains about dependencies, you can scan back through the output to find out what all needs to be installed. In the case of Clementine, you could always pick up the dependencies with the command:
sudo apt-get build-dep clementine
And there you go
That, my friends, is your introduction to installing from source. You might now not only have a better understanding as to how such an installation is handled, but why so many opt to bypass installing from source, and go straight to their distribution’s package manager. Dependency nightmares and a lack of consistency in steps helps to make the likes of apt, dpkg, yum, zypper, and dnfall the more appealing.
Yes, installing from source offers far more flexibility, but that flexibility comes at the price of simplicity.
Learn more about Linux through the free “Introduction to Linux” course from The Linux Foundation and edX.
This article is paid for by Huawei, a Platinum-level sponsor of Open Networking Summit, to be held April 3-6, and was written by Linux.com.
While the networking community is getting ready for Open Networking Summit 2017, we spoke to Bill Ren, Vice President of Huawei Network, Industry & Ecosystem Development, to discuss the role of openness in what Huawei calls the “All-Cloud Network.”
Bill Ren, Vice President of Huawei Network, Industry & Ecosystem Development
As companies grapple with digital transformation across all industries, Huawei advocates full cloudification to build efficient networks and agile competitiveness. “All-Cloud” Strategy involves a full reconstruction of network infrastructure, including equipment, network, services, and operations — and it will be built on openness.
“The future cloud network presents huge market potential. Full-gear and close collaboration from all industry parties is needed to build an industry ecosystem with positive impact and eventually, enable a successful rollout of the cloud network,” said Ren.
Indeed, in this big data and cloud age, collaboration and integration are the keystones of success.
That’s no secret to Huawei which is already heavily invested in pushing to shape cloud network-related standards, contributing on research results. The company is a founding Platinum member and major contributor to the OPNFV community, a Platinum member of The Linux Foundation, a Gold member of OpenStack and Cloud Foundry, and a founding member of ONOS.
“We fully participate in setting up SDN technical standards, as well as lead in setting up northbound interface / security / optical transmission and other standards.”
Here is what Ren had to say on how all that comes together to shape the future of the industry.
Linux.com: Why is cloud-network ecosystem so important to becoming and remaining competitive?
Ren: Currently, the whole industry is at a critical time of digital transformation. New technologies keep emerging, a flawless experience has become a requirement for end users, and an open and all-connected world has arrived. One can expect that the future will be a society that has thorough cross-industry integration and collaboration, which will need comprehensive network capacity.
Linux.com: Everyone agrees that innovation is crucial in the industry, but few are certain what that might look like. How does the future network differ from the networks that exist now?
Ren: In the past 20+ years, the world has built trillions of network assets. In order to maximize the value of these networks, to face the multiple challenges of intelligent society, and equip the network with the ability to build up the next one-trillion new business territory, the future network will have several features.
Linux.com: And what are those features? Or, at least some of them?
Ren: There are four main features: agility , intelligence, efficiency, and openness. By agility I mean the network must have the capability for quick integration of new services and new features, delivering a ROADS experiences and drastically reducing time-to-market (TTM).
By intelligence, I mean flexible and intelligent resource management, including fully automated planning, provisioning, resource allocation, and O&M to support thousands or even millions of service instances.
By efficiency, we mean better resource pooling. The industry must move away from closed silos, or the “chimney network model,” so that there is more sharing of resources and more ease in integration.
The fourth, of course, is openness. There must be more cooperation and participation by more industry partners to rapidly mature these technologies and to build larger pools of resources.
Open Networking Summit April 3-6 in Santa Clara, CA features over 75 sessions, workshops, and free training! Get in-depth training on up-and-coming technologies including AR/VR/IoT, orchestration, containers, and more.
Linux.com readers can register now with code LINUXRD5 for 5% off the attendee registration. Register now!
This article was sponsored by Huawei, a leading global information and communications technology (ICT) solutions provider. Our aim is to enrich life and improve efficiency through a better connected world, acting as a responsible corporate citizen, innovative enabler for the information society, and collaborative contributor to the industry. Driven by customer-centric innovation and open partnerships, Huawei has established an end-to-end ICT solutions portfolio that gives customers competitive advantages in telecom and enterprise networks, devices and cloud computing. For more information, please visit Huawei online at http://www.twitter.com/Huawei.
When containerization was young, one of its early principles was the ideal of immutable infrastructure,the ability to build a support structure for a container that was flexible enough to meet the container’s needs during its lifespan, which may be short, but remained a fixed asset throughout that duration.
It spoke to a possible, complete outmoding of one of IT’s most critical functions — configuration management — and a skill upon which enterprises dearly depend upon today. While the leading vendors in the space began discussing evolutionary adaptations, the practitioners in the space rallied together, forming a kind of global support group to keep hope alive through the evolutionary maelstrom.
