RHEL 8 New Features for Experienced Linux Administrators

On servera, verify that the python command does not exist by default on Red Hat Enterprise Linux 8.

1. Log in to servera then become the root user.

   [student@workstation ~]$ ssh servera
   [student@servera ~]$ sudo -i
   [root@servera ~]# 

2. Verify that the python command does not exist by default.

   [root@servera ~]# which python
   /usr/bin/which: no python in (/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin)

Install Python 2.7 and verify that it is available.

1. Use Yum to install Python 2.7 using the python27 module.

   [root@servera ~]# yum module install python27
   ...output omitted...
   Is this ok [y/N]: y
   ...output omitted...

2. Verify that Python 2.7 is available.

   [root@servera ~]# python2 -V
   Python 2.7.15

Install Python 3.6 and verify that it is available.

1. Use Yum to install Python 3.6 using the python36 module.

   [root@servera ~]# yum module install python36
   ...output omitted...
   Is this ok [y/N]: y
   ...output omitted...

2. Verify that Python 3.6 is available.

   [root@servera ~]# python3 -V
   Python 3.6.8

Use the alternatives command to enable /usr/bin/python3. When done, log off from servera.

1. Use the alternatives command to point /usr/bin/python to /usr/bin/python3.

   [root@servera ~]# alternatives --config python
   There are 3 programs which provide 'python'.
   
     Selection    Command
   -----------------------------------------------
   *+ 1           /usr/libexec/no-python
      2           /usr/bin/python3
      3           /usr/bin/python2
   
   Enter to keep the current selection[+], or type selection number: 3

2. Verify that the python command uses Python 3.6.

   [root@servera ~]# python -V
   Python 3.6.8

3. Log off from servera.

   [root@servera ~]# exit
   [student@servera ~]$ exit
   [student@workstation ~]$