Build on a clean CentOS image Centos image preparation Pull the Centos image on the virtual machine: docker pull centos Create a container to run the Centos image: docker run -it -d –name mycentos centos /bin/bash Note: There is an error here [ WARNING: IPv4 forwarding is disabled. Networking will not work. ]

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COPY and ADD commands in Dockerfile

Two very similar commands COPY and ADD are provided in the Dockerfile. This article attempts to explain the basic functions of these two commands, as well as their similarities and differences, and then summarize their respective suitable application scenarios.

Build context concept When you create a mirror from a […]

[root@ docker]# cat /etc/yum.repos.d/docker-main.repo [docker-main-repo] name=Docker main Repository baseurl=https://get.daocloud.io/docker/yum-repo/main/CentOS/7 enabled=1 gpgcheck=1 gpgkey=https://get.daocloud.io/docker/yum/gpg

[root@ docker]# yum install docker-engine –y

[root@ docker]# docker –version Docker version 17.05.0-ce, build 89658be

firewall-cmd –add-port=2377/tcp –permanent

firewall-cmd –add-port=7946/tcp –permanent

firewall-cmd –add-port=7946/udp –permanent

firewall-cmd –add-port=4789/udp –permanent

firewall-cmd –reload**

[root@ docker]# cat /etc/docker/daemon.json { “insecure-registries”:[“docker-registry.rmohan.com:5000”], “log-driver”:”json-file”, “log-opts”:{“max-size”:”1024m”,”max-file”:”2″} }

[root@ ~]# systemctl restart docker.service

[…]

Docker is an open source application container engine based on the  Go language  and open sourced under the Apache 2.0 protocol.

Docker allows developers to package their applications and dependencies into a lightweight, portable container that can then be published to any popular Linux machine or virtualized.

Containers are completely sandboxed and do not have any […]

Last login: Thu Mar 1 00:45:37 2018 from 192.168.1.248 [root@clusterserver1 ~]# uname -a Linux clusterserver1.rmohan.com 3.10.0-693.17.1.el7.x86_64 #1 SMP Thu Jan 25 20:13:58 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux [root@clusterserver1 ~]#

Master : 192.168.1.20 Worker1 : 192.168.1.21 Worker2 : 192.168.1.23 worker3 : 192.168.1.24

hostnamectl set-hostname ‘clusterserver1.rmohan.com’ exec bash setenforce 0 sed -i –follow-symlinks ‘s/SELINUX=enforcing/SELINUX=disabled/g’ /etc/sysconfig/selinux

[root@clusterserver1 […]