Managing CentOS Migrations and RHEL Upgrades

Instructions

In the this activity, you install the Convert2RHEL tool in the servera.lab.example.com server. The server is running a game as a web application, and that application must continue to operate correctly after the conversion of the servera machine. In a future activity, you will verify that the sample application still functions after the conversion.

After reviewing the web application, prepare and verify that your server is capable and ready for conversion. This preparation involves updating the server to the latest minor release, configuring repositories so that you can install conversion tooling, and identifying your activation key.

1. From the workstation machine, observe the demo application that is running on the servera CentOS Linux 7 machine. The application is a game that uses Node.js and some other operating system dependencies to function.

   Interact with the application to confirm that it is working correctly.

   1. Open a browser and navigate to the http://servera.lab.example.com site. Wait for the application to start.

   2. When the application finishes loading, press Space or click the web page to start playing.

      Press Space to prevent the bird from falling.

      When you are finished testing, close the web browser.

      After converting the system, you will test this application again in a future activity.

2. On the servera machine, confirm that your server's operating system is eligible for conversion.

   1. Log in to the servera machine as the student user. Switch to the root user. Use student as the password.

      [student@workstation ~]$ ssh servera
      student@servera's password: student
      [student@servera ~]$ sudo -i
      [sudo] password for student: student
      [root@servera ~]#

   2. Review the operating system version of the servera machine.

      [root@servera ~]# cat /etc/redhat-release
      CentOS Linux release 7.8.2003 (Core)

      You can convert this server. The release version is listed as 7.8, but the latest minor version of CentOS Linux 7 is 7.9. Later in this exercise, you will resolve this issue by updating the system.

3. Confirm that the servera machine's properties are supported for the conversion.

   1. Confirm that the operating system architecture is 64-bit Intel or AMD.

      [root@servera ~]# lscpu | grep -i mode
      CPU op-mode(s):        32-bit, 64-bit
      Model:                 85
      Model name:            Intel(R) Xeon(R) Gold 6248 CPU @ 2.50GHz

   2. Confirm that your server is not in FIPS mode.

      [root@servera ~]# cat /proc/sys/crypto/fips_enabled
      0

   3. Confirm that the system kernel modules are supported by RHEL.

      [root@servera ~]# lsmod
      Module                  Size  Used by
      nls_utf8               12557  0
      isofs                  39844  0
      nfit                   55639  0
      libnvdimm             159680  1 nfit
      iosf_mbi               15582  0
      ...output omitted...

      The installed modules on servera are supported. Review the modules that are installed in your organization's machines and open a support case to review the module list if necessary.

4. Configure the Convert2RHEL repository. Update the server and reboot it.

   1. In this lab environment, the Convert2RHEL repository is available in the local Satellite Server. This repository might not be available in your organization. However, you can download the GPG key and repository file from the Red Hat Customer Portal.

      Configure the Convert2RHEL repository by copying the /tmp/convert2rhel.repo file to the /etc/yum.repos.d/ directory.

      [root@servera ~]# cp /tmp/convert2rhel.repo /etc/yum.repos.d/

   2. Verify the contents of the /etc/yum.repos.d/convert2rhel.repo file.

      [root@servera ~]# cat /etc/yum.repos.d/convert2rhel.repo
      [convert2rhel]
      name=convert2rhel-for-rhel-7-rpms
      baseurl=http://satellite.lab.example.com/pulp/content/Operations/Library/custom/convert2rhel/convert2rhel-for-rhel-7-rpms/
      gpgcheck=0

   3. Update the servera machine packages.

      [root@servera ~]# yum update
      ...output omitted...
      Is this ok [y/d/N]: y
      ...output omitted...
      Complete!

   4. Reboot the servera machine.

      [root@servera ~]# reboot
      Connection to servera closed by remote host.
      Connection to servera closed.
      [student@workstation ~]$

      Wait a minute for the machine to reboot.

5. Install the Convert2RHEL tool.

   1. Log in to the servera machine as the student user. Switch to the root user. Use student as the password.

      [student@workstation ~]$ ssh servera
      student@servera's password: student
      [student@servera ~]$ sudo -i
      [sudo] password for student: student
      [root@servera ~]#

   2. Install the convert2rhel package.

      [root@servera ~]# yum install convert2rhel
      ...output omitted...
      Is this ok [y/d/N]: y
      ...output omitted...
      Complete!

   3. Review the convert2rhel command man page.

      [root@servera ~]# man convert2rhel
      ...output omitted...
      SUBCOMMANDS
          convert2rhel analyze
              Run all Convert2RHEL initial checks up until the Point of no Return (PONR)
              and generate a report with the findings.
              A rollback is initiated after the checks to put the system back
              in the original state.
      
          convert2rhel convert
              Convert the system. If no subcommand is given, 'convert' is used as a default.
      ...output omitted...

6. Exit the servera machine.

   [root@servera ~]# exit
   logout
   [student@servera ~]$ exit
   logout
   Connection to servera closed.