How to install Docker on CentOS 7 / RHEL 7

<div dir="ltr" style="text-align: left;" trbidi="on"> <span style="color: red; font-size: x-large;"><u><i>Install Docker on CentOS 7/RHEL7</i></u></span><br /> Docker is an <b>open-source tool that makes creating</b> & <b>managing Linux containers</b>(LXC) easy. Containers are like lightweight <b>VMs which can be started</b> & stopped in milliseconds. Dockers help the system admin & coders to develop their application in a container and can further scale up to 1000 of nodes.<br /> <br /> The main difference between container and <b>VM</b>(<b>Virtual machine</b>) is that dockers provide process based isolation , whereas VM provides full isolation of resources. Virtual machine takes a minute to start where as container can be started in a second or less than a second. Container uses the Kernel of host OS , whereas <b>VM</b> uses the separate Kernel.<br /> <div class="separator" style="clear: both; text-align: center;"> <a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh_e8ab3NUS91x2cNY9qtYM4PAwMpk4SFLzz9_apJXKNTeca1oBL9rEKSNyrfy3P_gUQr2LC29B3LWJWUeTnxeQG6w1sbZ9qoFeD2B1wi9GrwxRhvgXAlFYN1JLHw7IwJroLi9LZYokRuh9/s1600/docker_centos_www.hackthesec.co.in.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh_e8ab3NUS91x2cNY9qtYM4PAwMpk4SFLzz9_apJXKNTeca1oBL9rEKSNyrfy3P_gUQr2LC29B3LWJWUeTnxeQG6w1sbZ9qoFeD2B1wi9GrwxRhvgXAlFYN1JLHw7IwJroLi9LZYokRuh9/s1600/docker_centos_www.hackthesec.co.in.png" /></a></div> <br /> <br /> One of the limitation of <b>Docker</b> is that it can be used only on<b> 64bit hosts OS</b>.<br /> <br /> <br /> <span style="color: #073763; font-size: large;">Installation of Docker on CentOS 7</span><br /> <br /> Docker package is included in the default <a href="http://www.hackthesec.co.in/search/label/Centos">CentOS</a>-Extras repository. So to install docker , simply run below yum command :<br /> <br /> <span style="background-color: black;">[<span style="color: white;">root@localhost ~]# yum install docker</span></span><br /> <br /> <span style="color: #0b5394; font-size: large;"><u>Start the Docker Service</u></span><br /> <br /> Once the Installation is finished , start docker service and enable it at boot using below commands<br /> <span style="background-color: black;"><br /></span> <span style="background-color: black;"><span style="color: white;">[root@localhost ~]# service docker start</span></span><br /> <span style="background-color: black;"><span style="color: white;">[root@localhost ~]# chkconfig docker on</span></span><br /> <span style="background-color: black; color: white;"><br /></span> Download the official <a href="http://www.hackthesec.co.in/search/label/Centos">Centos</a> images Locally<br /> <br /> <div style="text-align: justify;"> [root@localhost ~]# <span style="color: blue;">docker pull centos</span></div> <div style="text-align: justify;"> Pulling repository centos</div> <div style="text-align: justify;"> 192178b11d36: Download complete </div> <div style="text-align: justify;"> 70441cac1ed5: Download complete </div> <div style="text-align: justify;"> ae0c2d0bdc10: Download complete </div> <div style="text-align: justify;"> 511136ea3c5a: Download complete </div> <div style="text-align: justify;"> 5b12ef8fd570: Download complete</div> <div style="text-align: justify;"> <br /></div> <div style="text-align: justify;"> <b> Verify CentOS images that have been fetched :</b></div> <div style="text-align: justify;"> <b><br /></b></div> <div style="text-align: justify;"> <b>[root@localhost ~]# docker images centos</b></div> <div style="text-align: justify;"> <b>REPOSITORY          TAG                 IMAGE ID            CREATED             VIRTUAL SIZE</b></div> <div style="text-align: justify;"> <b>centos                         centos5             192178b11d36        2 weeks ago         466.9 MB</b></div> <div style="text-align: justify;"> <b>centos                         centos6             70441cac1ed5        2 weeks ago         215.8 MB</b></div> <div style="text-align: justify;"> <b>centos                         centos7             ae0c2d0bdc10        2 weeks ago         224 MB</b></div> <div style="text-align: justify;"> <b></b></div> <div style="text-align: justify;"> <b>centos                          latest              ae0c2d0bdc10        2 weeks ago         224 MB</b></div> <br /> <u><b>Run a Docker Container :</b></u><br /> <u><br /></u> <span style="color: #cc0000;">[root@localhost ~]# <b>docker run -i -t centos /bin/bash</b></span><br /> <br /> <span style="color: #cc0000;">[root@dbf66395436d /]#</span><br /> <span style="color: #990000;"><br /></span> As we can see centos container has been started and we got the bash shell. In docker command we have used options like ‘-i attaches stdin and stdout’ and ‘-t allocates a terminal or console’ . To disconnect from container type exit .<br /> <br /> <span style="color: red;">[root@cd05639b3f5c /]# <b>cat /etc/</b></span><span style="color: #351c75;"><b>redhat-release</b> </span><br /> <span style="color: #0c343d;">CentOS Linux release 7.0.1406 (Core) </span><br /> <br /> <u><b>We can also search Containers based on fedora & ubuntu OS.</b></u><br /> <br /> <span style="color: red;">[root@localhost ~]# <b>docker search </b></span><span style="color: #7f6000;"><b>ubuntu</b></span><br /> <span style="color: red;">[root@localhost ~]# <b>docker search </b></span><span style="color: #7f6000;"><b>fedora</b></span><br /> <span style="color: #7f6000;"><b><br /></b></span> <span style="color: #7f6000;"><b><br /></b></span> <br /> <br /> <a href="http://www.hackthesec.co.in/">Hack The Sec</a><br /><a href="https://www.twitter.com/hackthesecurity">Hack The Sec Twitter</a><br /><span style="color: #999999; font-family: PT Serif, serif;"><span style="background-color: white; line-height: 22.3999996185303px;"><a href="https://www.facebook.com/htsecu">Hack The Facebook</a></span></span><br style="background-color: white; color: #333399; font-family: 'PT Serif', serif; font-size: 16px; line-height: 22.3999996185303px;" /><a href="http://linuxtutorial.net/">linuxtutorial.net</a><br /><span style="color: #999999; font-family: PT Serif, serif;"><span style="background-color: white; line-height: 22.3999996185303px;"><a href="http://hackthesec.co.in/">hackthesec.co.in</a></span></span><br /> <span style="color: #990000;"><br /></span></div>

How to install Docker on CentOS 7 / RHEL 7

Install Docker on CentOS 7/RHEL7 Docker is an open-source tool that makes creating & managing Linux containers (LXC) easy. Containers...

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