Basics of working with container and Docker realization of DevOps
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DevOps all the rage in the IT industry. Wikipedia describes DevOps is a set of practices that combine software development (Dev) and IT maintenance (Ops), designed to shorten the system development life cycle and provide high-quality continuous delivery. DevOps main reason for the popularity is that it enables organizations to develop and improve products faster than traditional software development methodologies.
With the changes in our working environment faster and faster, the demand for software development market in the fast delivery and repair is on the rise. Therefore, the output and limited production of high quality in a short time gave birth to the late error needs DevOps .
You may be interested in: Docker and DevOps: stateful application development and deployment in the Docker
As we have discussed the importance of DevOps into software development approach, we will now change the container of dialogue, which is an easy to use technology, are often used to implement DevOps is smoother and more convenient. It is a container of the DevOps practices easier to follow techniques. But the container of what in the end is? Let's find out!
What is containerized?
The container is the process of application and the desired library, and the frame profiles packaged together, so that it can be run efficiently in a variety of computing environments. Briefly, the container of the package is required and the application environment.
Recently, it has overcome the challenges brought about by running a virtual machine, which received widespread attention. The entire operating system inside a virtual machine simulation host operating system, and all the processes needed to run the operating system hardware allocation of a fixed percentage. Therefore, since a lot of overhead, which results in an unnecessary waste of computing resources.
At the same time, it takes time to set up a virtual machine, application-specific settings in each virtual machine process takes time. This results in only when the environment is set to spend a lot of time and effort. By the open source project "Docker" universal container of solving these problems, and by packaging the portable image file together with all required software dependencies, thereby improving portability.
Let us be more in-depth study of the vessel, benefits of using it, it works, select the tool container and how it's way better than a virtual machine (VM) is.
Some popular container provides procedures are as follows:
- Linux container, and LCD LXC e.g.
- Docker
- Windows Server container
What is the Docker?
Docker has become a popular term in the IT industry. Docker can be defined as an open source software platform that provides a building in the container, test, and deploy applications to protect the simplified method. Docker encourage software developers and cloud, Linux and Windows operating systems collaborate to quickly and easily deliver services.
Docker is to provide a container of the platform. It allows you to package your application and its dependencies into a container, thus helping to simplify development and speed up the deployment of the software. It eliminates the replication of the local environment on each machine should test solution needs to help achieve the maximum output, thus saving valuable time and energy, and these precious time and energy will be used for further development .
Dockerfile can quickly transfer and testing among staff. Docker also simplifies the process of container image management, and quickly changed the way we develop and test large-scale applications.
Containerized - to achieve DevOps
Docker has popularized the concept of the container. Docker container application has the ability to run multiple operating systems and cloud environment (e.g. Amazon ECS and the like). No technology or vendor limitations.
Let us understand the use of the container to achieve DevOps requirements.
Initially, the required software development, testing, deployment and supervision is carried out in stages, which will lead to the completion of a stage of the beginning of another phase.
Like AWS ECS, like, DevOps and Docker image management technology enables software developers can easily make IT operations, shareware and collaborate with each other, and improve productivity. In addition to encouraging developers to work together outside, they have succeeded in eliminating the conflicts between different environmental impact of the application before. In simple terms, the container is dynamic, it enables IT professionals without complicated to build, test and deployment pipeline, while bridging the gap between infrastructure and operating system release, thereby forming a DevOps culture.
Software developers can benefit from the container in the following ways:
- You can change the container's environment to better production deployment.
- Quick start and easy access to operating system resources.
- Unlike traditional systems, they provide enough space for the application to a suitable machine.
- To provide a DevOps agility, it can help to easily switch between multiple frames.
- Contribute to more effective operation of the workflow.
The following steps illustrate the use of Docker successful container to be followed:
- Developers should ensure that the code in the repository, such as Docker Hub.
- The code should compile correctly.
- Ensure proper packaging.
- Ensure that all plug-in requirements and dependencies.
- Docker to create a container using a mirror.
- Transfer it to any environment you choose.
- For ease of deployment, use the Rackspace, AWS and Azure and other cloud.
The benefits of using container
Many companies choose to bring the benefits of container. The following lists the advantages of using container technology will enjoy:
1. DevOps-friendly
The container of packaged with the application and environment dependence, in order to ensure a development environment application can work in another environment. This helps developers and testers to work together on the application, the entire contents of which is DevOps culture.
2. Clear platform
Containers can be run on GCS, Amazon ECS (elastic container service) and Amazon DevOps Server and other cloud platforms.
3. Portable born
Easy to carry container. Container image can easily be deployed to the new system, then you can share as files.
4. Faster scalability
Because of the isolation environment packed into a container, it can be quickly scalable, distributed applications for this program very helpful.
The need for a separate operating system
In the VM system, the host server's bare metal VM operating systems and different. In contrast, in the container, the mirror can be utilized Docker bare physical server host OS kernel. Therefore, the container has a higher efficiency than the virtual machine.
6. maximize resource utilization
Container of memory and computing resources may be utilized to maximize the CPU and the like, and the used resources is much less than VM.
7. A quick update application
With the rapid update of the application, delivery occurs in less time, making the platform easy to perform more system development. You can change the machine without rebooting resources.
Automatic scaling by means of the container can be considered complete in the machine's memory and CPU usage optimization case current load. And with the expansion of different virtual machines, without having to restart the computer to modify resource limits.
8. simplified security update
Since the container provides process isolation, and therefore maintain the security of the application has become more convenient.
9. Value for money
For to support a plurality of containers on a single base structure of the container is advantageous. Therefore, despite investment in tools, CPU, memory and storage, but for many companies, it is still a cost-effective solution.
DevOps achieve a complete workflow container allows software development teams benefit in the following ways:
- It provides the opportunity to perform automatic test at each step to detect the error function, so defects in the final product appears less.
- Faster and more convenient to deliver features and changes.
- The nature of the software more user-friendly than VM-based solutions.
- Reliable and changing environment.
- Promote collaboration and transparency between team members.
- Cost-effective nature.
- Ensure proper use of resources and reduce waste.
The difference between the container and the virtual machines (VMS)
Virtual machines can run multiple instances of a plurality of operating system on the host, but does not appear to overlap. Guest OS allows the host system to run as a single entity. Docker container does not generate as much burden on the system as a virtual machine running OS because of the need for additional resources, which will reduce the efficiency of the computer.
Docker containers will not increase the burden on the system, and use only the minimum resources needed to solve the running program, without having to simulate the whole operating system. Since Docker fewer resources required to run the application, it can allow a large number of applications running on the same hardware, thereby reducing the cost.
However, it reduces the isolation VM. It also increases the homogeneity, because if you run the application on a system Docker, then it will run without any fault on Docker on other systems.
Container and VM has a virtual mechanism. But for the container, it will be the operating system virtualization. In the latter, hardware virtualization.
VM limited performance, with a compact and dynamic Docker container is better performance.
VM needs more memory, it has more overhead compared to Docker containers, their large amount of computation.
Docker term
The following are some common terms Docker:
- Dependence - contains the library, the software required to form the frame and the environment, to simulate execution of the application medium.
- Mirror container - a software package, created to provide all the information required dependencies and container.
- Docker Hub - image hosting a public registry, where you can upload image and process it.
- Dockerfile - contains text about how to build Docker image documentation.
- Warehouse - based network or Internet-based services for storing Docker mirror, there are private and public Docker warehouse.
- Registry - A storage warehouse from multiple sources of service. It can be public can also be private.
- Docker Compose - a tool that can help define and run multiple applications Docker containers.
- Docker Swarm - machine cluster to run Docker created.
- Azure container Registry - a registry for storing image provider Docker
- Orchestrator - A method that facilitates simplified clustering and Docker host management tools.
- Docker Community Edition (CE) - tool provides a development environment for Windows and Linux container.
- Docker Enterprise Edition (EE) - Another set of tools for Linux and Windows development.
Docker containers, mirrors and registry
Use Docker create a service, and then package it in a container image. Docker mirroring services and their dependencies is a virtual representation.
Examples of the mirror is used to create a container, to run on the host Docker. Then the image is stored in the registry. The need for a registry to deploy to a production coordinator. Docker Hub is used to store it in its public registry at the framework level. Then the mirror and its dependencies to deploy their choice of environment. It is important to note that some private companies also provide the registry.
Commercial organizations can also create your own registry to store private Docker image. If the mirror is confidential and organizations want to deploy the delay between the mirror and the mirror image of the environment is limited, it can provide a private registry.
Docker containers of how to perform?
Docker mirrored container or application can run on Windows and Linux on locally. Docker engine simply by interacting directly with the operating system, you can use the system resources to achieve.
In order to manage the cluster, and combinations, Docker provided Docker Compose, it helps to run multiple applications without containers overlap each other. Developers can also connect to a single host all Docker by Docker Swarm virtual host mode. Thereafter, Docker Swarm to extend applications to multiple hosts.
Thanks Docker containers, component developers can access the container, such as applications and dependencies. Developers also have the framework of the application. A plurality of containers on a single platform and interdependent called "deployment manifest." However, at the same time, professionals can pay more attention to selecting the right environment to deploy, expand and monitor. Docker helps limit the chance of error, the chance of errors may occur during application transfer.
After the completion of local deployment, they will be sent to further Git repository code repository or the like. Dockerfile code repository for constructing the continuous integration (CI) line, to extract the base container and build Docker mirror image.
In DevOps mechanism, the developer is committed to transfer files to multiple environments, and management professionals are responsible for managing the environment in order to check for defects and send feedback to developers.
Strategy for the future container
Predict and prepare for future scalability needs of the project is always a good idea. Over time, the project becomes more complex, it is necessary to implement large-scale automation and provide faster delivery.
Dense and complex environment requires appropriate container processing. In this case, software developers can use PaaS solutions to put more focus on coding. When you select the most convenient platform to provide better and advanced services, there are a variety of options. Therefore, to determine the correct application platform based on the organization's very troublesome.
For your convenience, we have before selecting the best container platform has a list of some parameters to consider:
1. The flexible nature
In order to obtain a smooth performance, it is important to manually pick up a platform that can be easily adjusted or modified according to the properties of the needs, and can be automated.
2. Lock level
In fact, PaaS solutions are usually proprietary, and therefore tend to lock you in one infrastructure.
3. Innovation Space
Select a platform should have a wide range of built-in tools and third-party integration technology to encourage developers to make way for further innovation.
4. Cloud Support Options
When choosing the right platform, it is essential to find a private, public and hybrid cloud deployment platform support, to cope with the new changes.
5. Pricing Model
Since the selection of long-term commitment to support the container platform is natural, and therefore understand what is important to provide pricing model. There are many platforms can offer different pricing models on a different scale of operations.
6. The time and effort
Another key aspect to remember is that containerized not happen overnight. Professionals need to spend time re-organization infrastructure. They should be encouraged to run micro-services.
To shift from the conventional structure, large applications need to break into smaller portions, and then further distributed to those portions of the plurality of connected containers. Therefore, it is recommended to hire experts, they will make every effort to find a convenient solution to handle virtual machines and containers on a single platform, because the tissue is completely dependent on the container needs time.
7. compatibility with legacy applications
When it comes to modernization, it should not be overlooked legacy IT applications. With the help of the vessel, IT professionals can use the proceeds of these classic applications to properly utilize investments in the old framework.
8. Multi-Application Management
By running multiple applications on the container platform to take advantage of the container. At the lowest cost to invest in new applications, and to be modified for each platform by making it current and legacy applications-friendly.
9. Security
Since the container environment faster than traditional environments the ability to change, so it has some major security risk. Agility can enable developers to benefit by providing fast access. However, if you can not ensure the level of security required, it will fail.
A major problem encountered when processing container is processed packaged by a third party or untrusted source container template may bring great risk. Therefore, the best validation templates publicly available before use.
Organizations need to strengthen and integrate its security processes to worry develop and deliver applications and services. With the modernization of platforms and applications, security should be a corporate priority.
in conclusion
To keep pace with the rapidly changing IT industry, professionals should be constant pursuit of better, therefore, the new tools available on the market should be used to enhance security.
This marks the conclusion of Part 2! In Part 3, we will discuss the key DevOps DevOps tools and implementation strategies.
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Author Mitul Makadia