Shulou(Shulou.com)06/01 Report--

How to install Docker and FastDFS? Many novices are not very clear about this. In order to help you solve this problem, the following small series will explain it in detail for everyone. Those who have this need can come to learn. I hope you can gain something.

Docker Features

1) Get started quickly

Users can "Docker" their programs in just a few minutes. Docker relies on a copy-on-write model, which makes it possible to modify applications very quickly, so to speak, to the point of "changing code at will."

You can then create containers to run your application. Most Docker containers take less than 1 second to start. Docker containers have high performance because of the overhead of the hypervisor, and more containers can be run on the same host, allowing users to make the most of system resources.

2) Logical classification of responsibilities

With Docker, developers only need to care about the applications running in containers, and operations staff only need to care about how to manage containers. Docker is designed to enhance consistency between the development environment in which developers write code and the production environment in which applications are deployed. Thus reducing the kind of "everything is normal during development, it must be an operation and maintenance problem (the test environment is normal, and if there is a problem after launch, it must be an operation and maintenance problem)"

3) Fast and efficient development lifecycle

One of Docker's goals is to shorten the code cycle from development, testing, deployment, and go-live, making your applications portable, easy to build, and easy to collaborate on. (In layman's terms, Docker is like a box, which can hold many objects. If you need these objects, you can directly take away the big box without taking them one by one from the box.)

4) Encourage the use of service-oriented architecture

Docker also encourages service-oriented architecture and microservice architecture. Docker recommends running only one application or process in a single container, thus forming a distributed application model in which applications or services can be represented as a series of interconnected containers, making it easy to deploy applications, scale or debug applications in a distributed manner, and improving the introspection of the program. (Of course, you can run multiple applications in one container)

What to do with Docker

Containers provide isolation, and containers can provide a nice sandbox environment for a variety of tests. And the container itself.

They have the characteristics of "standardization" and are ideal for creating building blocks for services. Some of Docker's application scenarios are as follows:

Accelerate local development and build processes to make them more efficient and lightweight. Local developers can build, run, and share Docker containers. Containers can be built in a development environment, then easily committed to a test environment, and eventually into production.

It enables independent services or applications to get the same results in different environments. This point in service-oriented architecture and heavy reliance on microservices deployment by its utility.

Docker creates isolated environments for testing. For example, start a container for testing with a continuous integration tool like Jenkins CI.

Docker allows developers to build a complex program or architecture natively for testing, rather than deploying and testing it in production from the start.

installation and operation

1. Installing Docker in Ubuntu

Update apt source index for ubuntu

sudo apt-get update

Installation package allows apt to use repositories over HTTPS

sudo apt-get install \ apt-transport-https \ ca-certificates \ curl \ software-properties-common

Add Docker official GPG key

curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -

Set up Docker stable repository

sudo add-apt-repository \ "deb [arch=amd64] https://download.docker.com/linux/ubuntu \ $(lsb_release -cs) \ stable"

Update apt source index after adding repository

sudo apt-get update

Install the latest Docker CE (Community Edition)

sudo apt-get install docker-ce

Check if Docker CE is installed correctly

sudo docker run hello-world

The following message appears, indicating successful installation

In order to avoid entering sudo every time, you can set user permissions. Note that you must log out and log in again after execution.

sudo usermod -a -G docker $USER

2. start and stop

After Docker is installed, docker service has been started by default. To manually control the start and stop of docker service, you can execute the following command

#Start dockersudo service docker start#Stop dockersudo service docker stop#Restart dockersudo service docker restart

3. Docker image operations

1. List Mirrors

docker image ls

2. pull images from the nearest region

To get an image, we can pull it locally from the repository using the pull command, such as

docker image pull library/hello-world

Since the image files provided by Docker are all placed in the library group, it is the default group and can be omitted. Therefore, the above command can be written as follows.

docker image pull hello-world

3. removing mirroring

docker image rm image name or image id

4. Docker container operations

create a container

docker run [option] image name [command passed into boot container]

Common optional parameters:

-i means to run the container in interactive mode

-t indicates that the container will enter its command line after startup. After adding these two parameters, the container creation can log in. i. e. assign a dummy terminal.

--name Name the container you created

-v represents directory mapping relationship (the former is host directory, the latter is mapped to the directory on the host, i.e. host directory: directory in container), you can use multiple-v to do multiple directory or file mapping. Note: It's best to map directories, make changes on the host, and then share them to containers.

-d Add the-d parameter after run, and a daemon container will be created to run in the background (so that the container will not automatically log in after creation, if only add-i -t two parameters, it will automatically enter the container after creation).

-p indicates port mapping, the former is host port, the latter is mapped port within container. Multiple port mappings can be done using multiple-p

-e Sets environment variables for containers

--network=host means mapping the network environment of the host to the container, and the network of the container is the same as that of the host

interactive container

For example, create an interactive container and name it myubuntu

docker run -it --name=myubuntu ubuntu /bin/bash

Linux commands can be executed freely in the container, which is an ubuntu environment. When the exit command is executed, the container stops.

guard vessel

Create a Daemon Container: If for a container that needs to run for a long time, we can create a Daemon Container. The container does not stop when the container exits inside.

docker run -dit --name=myubuntu2 ubuntu

Enter already running container

docker exec -it container name or container id The first command executed after entering

as

docker exec -it myubuntu2 /bin/bash

View containers

#List the containers docker container ls is running #List all containers docker container ls is running, including docker container ls --all

Stop and Start Container

#Stop a running container docker container stop container name or container id#Start a stopped container docker container start container name or container id#Kill a running container docker container kill container name or container id

delete a container

docker container rm container name or container id

5. Save container as mirror

We can save the container as a mirror with the following command

docker commit container name image name

6. Mirror Backup and Migration

We can use the save command to package the image into a file and copy it to others for use.

docker save -o save file name image name

as

docker save -o ./ ubuntu.tar ubuntu

After getting the image file, you can load the image locally by using the load method.

docker load -i ./ ubuntu.tar

Installing FastDFS with Docker

1. obtain image

FastDFS can be run using an existing FastDFS Docker image.

Images can be obtained by downloading

docker image pull delron/fastdfs

After loading the image, you can start the tracker and storage running FastDFS.

2. Run tracker

Run the following command to start the tracker service

docker run -dti --network=host --name tracker -v /var/fdfs/tracker:/var/fdfs delron/fastdfs tracker

We map the fastDFS tracker run directory to the local/var/fdfs/tracker directory.

Run the following command to see if tracker works

docker container ls

To stop the tracker service, execute the following command

docker container stop tracker

After stopping, restart tracker and execute the following command

docker container start tracker

3. running storage

Run the following command to start the storage service

docker run -dti --network=host --name storage -e TRACKER_SERVER=10.211.55.5:22122 -v /var/fdfs/storage:/var/fdfs delron/fastdfs storage

TRACKER_SERVER= IP address:22122 IP address: 127.0.0.1

We map the fastDFS storage run directory to the local/var/fdfs/storage directory

Run the following command to see if storage is working

docker container ls

To stop the storage service, execute the following command

docker container stop storage

After stopping, restart storage by executing the following command

docker container start storage

Note: If you cannot rerun, delete the fdfs_stored.pid file in the/var/fdfs/storage/data directory and rerun storage.

Did reading the above help you? If you still want to have further understanding of related knowledge or read more related articles, please pay attention to the industry information channel, thank you for your support.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.