DevOpsCategory

This document explains how to secure private repository using openssl key Before we can use a private repository, we will need to secure it and offer user authentication. Let’s create a self-signed certificate, use the ‘registry’ container by Docker to create basic user authentication, and then copy the files where… Continue Reading DOCKER CONCEPT FOR DBA– PART 10 : How to secure docker private repository using openssl certificate key

1.Creating docker tar file from docker image.We can transfer that tar file and import to another docker instance. root@deb-VirtualBox:~# docker image save mywebserver:v1>mywebserver.tar root@deb-VirtualBox:~# ls -ltr mywebserver.tar -rw-r–r– 1 root root 330399232 May 2 19:53 mywebserver.tar 2.Remove the existing docker image  root@deb-VirtualBox:~# docker rmi -f mywebserver:v1 Untagged: mywebserver:v1 3.Please note… Continue Reading DOCKER CONCEPT FOR DBA– PART 9 : How to use docker tar command in docker to re-instantiate new docker

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… Continue Reading DOCKER CONCEPT FOR DBA – PART 8 How to build docker image from docker file

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:… Continue Reading DOCKER CONCEPT FOR DBA – PART 7 Pull docker image from repository

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… Continue Reading DOCKER CONCEPT FOR DBA – PART 6 Installation of docker UCP

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… Continue Reading DOCKER CONCEPT FOR DBA– PART 5 Installation of Docker Swarm

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… Continue Reading Docker concept for DBA- part 4 Install demo docker and test

DOCKER Use the Device Mapper storage driver Device Mapper is a kernel-based framework that underpins many advanced volume management technologies on Linux. Docker’s devicemapper storage driver leverages the thin provisioning and snapshot capabilities of this framework for image and container management. This article refers to the Device Mapper storage driver as devicemapper, and… Continue Reading DOCKER CONCEPT FOR DBA -PART 3 device mapper for Dcoker

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… Continue Reading docker concept for DBA-part-2 Run docker for non-privileged user (Other than root)

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:… Continue Reading Docker concept -part 1-Concept and Installation of docker in CentOS