CentOS for Work

I came across Linux in 2005, it was Debian. Then followed a love affair with Ubuntu, for which in March 2009 I purchased a netbook Asus EeePC 1000. In 2010, I began to contribute to ALT Linux participating in the “School Project” and even became a basic256 package maintainer.

The last few years my EeePC with Ubuntu peacefully rested deep in my cupboard. Then there was a chance to clean off the dust. There was a task to get acquainted with CentOS Linux and test examples for my webinar “Apache Ant – quick start”.

Visiting centos.org, I stop at version 6.8. On http://isoredirect.centos.org/altarch/7/isos/i386/ page I selected the server with disk images and download files CentOS-6.8-i386-LiveCD.iso. With the help of Rufus create a bootable USB and successfully install the CentOS 6.8 on my Asus EeePC. The process is very simple. The dark-blue colors of the good old GNOME are pleasing to my eyes.

What tools (programs/packages) do I need? So far, I need only three: Java JDK, Apache Ant, and Git. I begin to synchronize and update package index files, keeping in mind that instead of apt-get (in Ubuntu) on CentOS they use yum:

[lamp@localhost ~]$ sudo yum update
[sudo] password for lamp:
lamp is not in the sudoers file. This incident will be reported.

Here is the news… Unlike Ubuntu, the unprivileged user cannot use by default via sudo the commands with root privilege. Learning https://wiki.centos.org/TipsAndTricks/BecomingRoot I decide to use the “quick and dirty way” by editing the file /etc/sudoers. To do this the root has visudo command (thanks to tips of experienced colleagues). I pass on in the root account (after su command I enter the root password, which I have set during the installation):

[lamp@localhost ~]$ su
[root@localhost lamp]# visudo

I find the line “root ALL=(ALL) ALL” in the file and add (pre-pressing the “I” and entering into insert mode) a similar line, but instead of root I'm writing lamp, it turns this way:

root ALL=(ALL) ALL
lamp ALL=(ALL) ALL

I press Esc and go out with saving (:wq). I leave root account using exit. Now I can give privilege using sudo and my password. And I repeat:

[lamp@localhost ~]$ sudo yum update
[sudo] password for lamp:

I enter my password, everything works. The yum updates indexes, and offers to upgrade some packages by downloading about 197 MB. I answer N (No); it can wait a little.

Time turn to Java JDK. In front of me, there is a dilemma: install the oracle-jdk or openjdk. Thanks to the advice of more experienced colleagues I'm inclined to get openjdk. I use the command yum search to find the name of the package to be installed. Surely, I take the latest version:

[lamp@localhost ~]$ sudo yum search jdk
java-1.8.0-openjdk-devel.i686 : OpenJDK Development Environment
[lamp@localhost ~]$ sudo yum install java-1.8.0-openjdk-devel
[lamp@localhost ~]$ javac -version
javac 1.8.0_121
[lamp@localhost ~]$ java -version
openjdk version "1.8.0_121"
OpenJDK Runtime Environment (build 1.8.0_121-b13)
OpenJDK Server VM (build 25.121-b13, mixed mode)

JDK is there, now it is the time for Apache Ant. I'm trying to get it from a repository:

[lamp@localhost ~]$ sudo yum install ant

…in addition, yum offers to download about 60 MB and install 10 dependency packages, where ant takes only 2.2 MB. However, Google slightly hints – is will be the version 1.7.1 which does not suit me at all (it nas no junit). After a short search, I find a suitable script that allows me to download and install the latest version. I edit it a little for myself:

# download and install
wget ${antserver}/ant/binaries/${antname}-${antversion}-bin.tar.gz
sudo tar xvfvz ${antname}-${antversion}-bin.tar.gz -C /opt
sudo ln -sfn /opt/${antname}-${antversion} /opt/ant
sudo sh -c 'echo ANT_HOME=/opt/ant >> /etc/environment'
sudo ln -sfn /opt/ant/bin/ant /usr/bin/ant

# check installation
ant -version

# cleanup
rm ${antname}-${antversion}-bin.tar.gz

I save the script in the home directory and then run:

[lamp@localhost ~]$ chnod +x installantoncentos.sh
[lamp@localhost ~]$ ./installantoncentos.sh

I see the last line, which is the result of ant -version command:

Apache Ant(TM) version 1.10.1 compiled on February 2 2017

I take Git from the repository:

[lamp@localhost ~]$ sudo yum install git
[lamp@localhost ~]$ git --version
git version 1.7.1

So, the tools are ready and I can start testing examples for my webinar. But this is another story…

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Last updated: October 20, 2023