Docker one. Know Docker

A. about Docker

1.1 What is Docker

First, Docker is an open-source " container-level " virtualization technology.

1.2 What is " Container-level "Virtualization Technology

when it comes to container-level virtualization, it's important to first say "LXC""LXC"The Legacy container-level virtualization technology is developed by IBM and Docker is in theLXC"on the basis. The container level can be understood as the Linux system is a large box and Docker is the small box inside the big box, running in the big box Linux but isolated from the large box. Just like the sandbox running inside the WinDOS , the truth is the same. Docker is based on systems, but standalone systems.

1.3 Docker 's goal

The purpose of the Docker project is to achieve Lightweight Operating system virtualization solution , and consumes less resources.

1.4 Why use docker Docker why so hot

As an emerging virtualization approach, Docker has a number of advantages over traditional virtualization approaches.

First, the launch of the Docker container can be implemented in seconds, which is much faster than the traditional virtual machine approach. Second, Docker is highly utilized for system resources and can run thousands of Docker containers simultaneously on a single host.

In addition to running applications, the container does not consume any additional system resources, which makes the performance of the application very high and the overhead of the system as small as possible. Traditional virtual machines run 10 different applications with 10 virtual machines, and Docker only needs to start 10 isolated applications.

Specifically, Docker has a big advantage in the following areas.

1.4.1Faster delivery and deployment

The most desirable thing for development and OPS people is to create or configure one at a time, and to work properly anywhere.

Developers can use a standard image to build a set of development containers that, when developed, can be used directly by the OPS to deploy the code. Docker can quickly create containers, quickly iterate applications, and make the entire process visible, making it easier for other members of the team to understand how the application was created and worked. Docker containers are very light and fast! The start time of the container is second-level, which saves the time of development, testing and deployment greatly.

1.4.2more efficient Virtualization

The Docker container runs without additional hypervisor support, which is a kernel-level virtualization that enables higher performance and efficiency.

easier migrations and extensions

Docker containers can run on virtually any platform, including physical machines, virtual machines, public clouds, private clouds, personal computers, servers, and more. This compatibility allows the user to migrate an application directly from one platform to another.

1.4.3more Simple Management

With Docker, you can replace a lot of previous updates with just a little bit of modification. All modifications are distributed and updated incrementally, enabling automation and efficient management.

1.4.4Compare traditional virtual machine summaries

650) this.width=650; "src=" Http://s3.51cto.com/wyfs02/M02/6B/FE/wKioL1U9mYWDhvbUAACnOWtqfxU024.jpg "title=" QQ picture 20150427100118.png "alt=" Wkiol1u9mywdhvbuaacnowtqfxu024.jpg "/>

1.5 Docker Usage Scenarios

 DOcker Use of the scene, the existing server resource consumption ratio is relatively small , For example (a simple Web Server, you can put several Docker containers for load balancing, failover clustering). Does not apply to existing servers that occupy large resources such as (HPC cluster, large database orcle)

By the way, not all services are suitable for migrating to virtualized platforms, depending on the size of the server resources that are consumed by the service.

advantages and disadvantages of 1.6 docker

Advantages: Take up the system resources small startup speed up the system hard drive small fast generation "Templates"quickly generate multiple based on templates"Container"in performance close to the acoustic system,Docker is open source for many businesses that support Docker such as redhat openstart , ETC., Fast migration, rapid deployment, and more efficient operations.

Cons: Now the latest version of Docker is 1.6 compared to established virtualization software,Docker technology is relatively immature, Docker still has a certain number of bugs with relatively few users, fewer documents, and no post-sale support.

Reference document "Docker Technology Introduction and Combat", and my Views and views on Docker

QQ:786376668,4309617

Xiao Peng

Email: [email protected]

You are welcome to study Docker with me.

This article is from the "Linux" blog, so be sure to keep this source http://3927416.blog.51cto.com/3917416/1638955

Docker one. Know Docker