Install PIP on CentOS 7

Python is widely used programing language and pip is the tool need to install different python packages.

Before you go ahead check if you have pip installed by using command below.

 $ pip --version 
 pip 9.0.1 from /Library/Python/2.7/site-packages (python 2.7)

You can install pip in multiple ways on CentOS. I will discuss here two ways to install pip. 

Install PIP using yup

Update the packages first, just to be updated.

$ yum -y update

Once update is complete, you can run below command to install the pip. 

$ yum -y install python-pip

If you get error, did not found anything to install python-pip then you need to enable Extra Packages for Enterprise Linux (EPEL) repository, as python-pip is part of EPEL repo. If you don't want to enable EPEL repo then you can use other installation method.

Install PIP using curl

First step is to download the python script to install pip. 

$ curl "https://bootstrap.pypa.io/get-pip.py" -o "get-pip.py"

Once the script is downloaded you can run below command to install pip.

$ python get-pip.py

If you get permission error or write error run above command using sudo. 

Setup python 2.7 on CentOS 7

Python is most commonly used development and scripting tool. You can setup Python on CentOS by multiple ways.

Setup Python using Yum

This is simplest method to install development tools on CentOS. Run below commands to setup the python using yum.

[vagrant@localhost ~]$ sudo yum -y update
[vagrant@localhost ~]$ sudo yum groupinstall -y development

Or

[vagrant@localhost ~]$ sudo yum groupinstall -y 'development tools'

Setup Python using source code

To setup python using source code, you would first download the source code for the version you want to install. Then build the source code and configure.

You can use "wget" command to download the compressed source code. If you don't have wget installed, use yum to install wget as below.

[vagrant@localhost ~]$ sudo yum install wget

You would need "xz" tool to decode the source code.

[vagrant@localhost ~]$ sudo yum install xz-libs

Now you are ready to download the source code. 
Download the source code for python 2.7.6 using below command. You can choose which version you want to install and download sources from here.

[vagrant@localhost ~]$ wget http://www.python.org/ftp/python/2.7.6/Python-2.7.6.tar.xz

Decode the archive then extract using below command.

[vagrant@localhost ~]$ xz -d Python-2.7.6.tar.xz
[vagrant@localhost ~]$ tar -xvf Python-2.7.6.tar

Traverse to extracted python source code directory then run configure.

[vagrant@localhost ~]$ cd Python-2.7.6
[vagrant@localhost ~]$ ./configure --prefix=/usr/local

Run 'make install' build the source and install the binaries. You can also use the 'altinstall' to replace older installation.

[vagrant@localhost ~]$ make altinstall

Once the installation complete, you can verify installation by running the python command. If you get the command not found then update the path variable as below.

[vagrant@localhost ~]$ export PATH="/usr/local/bin:$PATH"

Now your python is setup for use.

How to Install Java 8 on CentOS 7

Java is most common requirement for many of the Open Source softwares. You can follow below steps to install Java on CentOS vm.

You can first check the list of available packages for Java using below command.

$ yum search java | grep 'java-'

You will get the list like above. Now depending on what is your requirement you can choose the package. If you don't see any list as above, you will need to update the REPO for java.

To install JRE you can run below command.

$ sudo yum install java-1.8.0-openjdk.x86_64

To install JDK you can use below command.

$ sudo yum install java-1.8.0-openjdk*

The above commands will ask for downloading the required dependencies, press Y and enter to continue with installation. Once installation completes it will display the dependencies installed and complete message.

Now you can verify the installation by running below command.

$ java -version

openjdk version "1.8.0_144"

OpenJDK Runtime Environment (build 1.8.0_144-b01)

OpenJDK 64-Bit Server VM (build 25.144-b01, mixed mode) 

You should see the java version as shown in above output.

Setup CentOS 7 VM on VirtualBox

This is step by step guide which will let you run the CentOS 7 VM on your virtual box installation. In this tutorials are illustrated using Mac.

Installing VirtualBox

VirtualBox is a powerful x86 and AMD64/Intel64 virtualization product for enterprise as well as home use

• Make sure your if your machine allows virtualization. Check your host OS is supported for Virtualbox
• Download VirtualBox from the here. Install the VirtualBox. Check the installation by running below command. 

Installing Vagrant

Vagrant manages virtual machines hosted in Oracle VirtualBox. A virtual machine is a software implementation of a computer, running a complete operating system stack on a virtualizer.

• Download Vagrant from here. Install the vagrant.
• Check the installation by running below command.

Setup CentOS VM

Once you are done with vagrant, now you are ready to setup your CentOS VM. 

Run below command, which will create "vagrantfile" under the current working directory. The vagrantfile can be used to configure and provision the VM.

Once you see above message you can run "vagrant up" command, which will pull the CentOS image and create a VM under virtual box, as shown in below image.

Connecting to VM

Once the CentOS is up successfully, you can check in the VirtualBox its setting as well as you can change those.

If CentOS is running then you can connect VM via ssh using below command.

Now your CentOS VM is ready to use.

You can take a snapshot of VM before use, so it can be discarded anytime and clean VM will be ready to use. You can also delete the VM using Virtualbox as well. 

Installing MariaDB 10.1 on CentOS 6

Inorder to install MariaDB 10.1 you nned to have your MariaDB.repo entry. So create a file "/etc/yum.repos.d/MariaDB.repo" under "/etc/yum.repos.d/" directory.
Update the MariaDB.repo file with below text for 64bit OS

[mariadb]
name = MariaDB
baseurl = http://yum.mariadb.org/10.1/centos6-amd64
gpgkey=https://yum.mariadb.org/RPM-GPG-KEY-MariaDB
gpgcheck=1

Update the MariaDB.repo file with below text for 32bit OS
`

[mariadb]
name = MariaDB
baseurl = http://yum.mariadb.org/10.1/centos6-x86
gpgkey=https://yum.mariadb.org/RPM-GPG-KEY-MariaDB
gpgcheck=1

Now run below command just to check if the repo is set correctly.

#sudo yum search Mariadb 

Now install MariaDB using below command

# yum install MariaDB-server MariaDB*engine MariaDB-client

Error: No package erlang available.

If you are trying to install Erlang on CentOS 6.x or 5.x you might get below errors

[root@abcdef install]# yum install erlang

Failed to set locale, defaulting to C

Loaded plugins: fastestmirror, refresh-packagekit, security

Loading mirror speeds from cached hostfile

 * base: centos.mbni.med.umich.edu

 * extras: mirror.linux.duke.edu

 * updates: mirror.linux.duke.edu

Setting up Install Process

No package erlang available.

Error: Nothing to do

If you are getting these errors mean you don't have RHEL EPEL Repo updated to fetch Erlang builds. So you will need to update your repo. 

CentOS 5.x :

wget http://dl.fedoraproject.org/pub/epel/5/x86_64/epel-release-5-4.noarch.rpm

wget http://rpms.famillecollet.com/enterprise/remi-release-5.rpm

sudo rpm -Uvh remi-release-5*.rpm epel-release-5*.rpm

CentOS 6.x :

wget http://dl.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm

wget http://rpms.famillecollet.com/enterprise/remi-release-6.rpm

sudo rpm -Uvh remi-release-6*.rpm epel-release-6*.rpm

Now You can try installing Erlang with command below

# yum install -y erlang