1.You need to create docker file first.Below is example of small test docker file. root@deb-VirtualBox:~# cat test_docker.file FROM centos:latest RUN yum update -y Here please note that FROM clause denotes first we need to pull centos image and RUN clause will run yum update on top of it. 2.Now I will build the docker image . -t option is used […]
Docker hub is repository of images for Community Edition. 1.Checking docker images available in server [root@debasiseric3 ~]# docker images REPOSITORY TAG IMAGE ID CREATED SIZE 2.Let me try to pull a demo project [root@debasiseric3 ~]# docker pull hello-world Using default tag: latest latest: Pulling from library/hello-world 9bb5a5d4561a: Pull complete Digest: sha256:f5233545e43561214ca4891fd1157e1c3c563316ed8e237750d59bde73361e77 Status: Downloaded newer image for hello-world:latest 3.Let me check […]
This document will explain docker UCP for Enterprise grade cluster management What is Docker UCP Docker Universal Control Plane (UCP) is the enterprise-grade cluster management solution from Docker. You install it on-premises or in your virtual private cloud, and it helps you manage your Docker swarm and applications through a single interface. Universal Control Plane is a containerized application that […]
What is a docker swarm? A swarm consists of multiple Docker hosts which run in swarm mode and act as managers (to manage membership and delegation) and workers (which run swarm services). A given Docker host can be a manager, a worker, or perform both roles. When you create a service, you define its optimal state (number of replicas, network and storage resources […]
Docker concept – part 4 Install demo docker and test [user@debasiseric1 ~]$ sudo su – [sudo] password for user: Last login: Mon Apr 9 12:20:36 UTC 2018 on pts/0 [root@debasiseric1 ~]# cd /etc/docker [root@debasiseric1 docker]# docker images REPOSITORY TAG IMAGE ID CREATED SIZE centos 6 70b5d81549ec 3 days ago 195MB We need to pull the httpd demo docker image [root@debasiseric1 […]
You need to change group to docker for user (non-privileged user) otherwise you get following error:- [user@debasiseric1 ~]$ docker images Got permission denied while trying to connect to the Docker daemon socket at unix:///var/run/docker.sock: Get http://%2Fvar%2Frun%2Fdocker.sock/v1.37/images/json: dial unix /var/run/docker.sock: connect: permission denied Now I will login to root sudo su – cd /var/run [root@debasiseric1 run]# ls -al docker.sock srw-rw—- 1 […]
A. Basic Concept of docker Docker is a platform for developers and sysadmins to develop, deploy, and run applications with containers. The use of Linux containers to deploy applications is called containerization. Containers are not new, but their use for easily deploying applications is. Containerization is increasingly popular because containers are: Flexible: Even the most complex applications can be containerized. Lightweight: Containers […]