Objective:  REHL 6 to CentOS 7 Migration of Splunk Architecture

Note: IP and hostname of New VM with CentOS 7 should be made same as of Old VM. So that it will replace Old VM in architecture.

  • Check firewall setting after migration is done.
  • Check cluster architecture functionalities post migration.

Updating OS of Splunk Instance-> All requisite commands are highlighted, this task was specifically performed on Splunk instances with REHL6 to migrate Splunk VM’s to CENTOS 7. We have distributed clustered architecture.

Create New Centos 7 VM through below process, here we are Creating replica via Existing VM Template.

Note: Also, you can download OS Centos7 and install.


Now for New VM with updated OS, login and check IP address assigned to it automatically i.e. 192.168.0.64

 

Note: Use this step only if the New VM is created by replica of existing VM template, else skip it.

Now change its UUID by editing ifcfg-ethi file, as it is created by snapshot of another instance:

  • UUID path-   cd /etc/sysconfig/network-scripts
  • Edit UUID file-vi ifcfg-ethi
  • Update UUID (replace few characters only, total characters in UUID must be same before and after edit)
  • Restart instance- systemctl restart network
Meanwhile showing ifcfg-ethi file where we edit UUID.
 
Login New VM to check Sudoer working or not (This step is specific as per task).
 

Log in to OLD VM and stop Splunk running on this instance.

 
Switch to root user and TAR Splunk home directory of Old VM.

Once it gets TAR completely, check a file is reflecting with .tar in opt.

 

Copy Tar file from Old VM to New VM, Using scp command.

Login to New VM and extract Splunk directory .tar file at opt directory.
 
Now we need to change the hostname of New VM as Old VM, by login as root.

Also change IP of New VM as Old VM by Firewall.
Verify hostname and IP that we changed for New VM, by login as root.
 
Once all post checks are done and all running well, start New VM Splunk and make sure Old VM Splunk is permanently stopped.

 

Study Material: Kindly click here and refer doc for more details.

If you are still facing issue regarding REHL 6 to CentOS 7 Migration Feel free to Ask Doubts in the Comment Box Below and Don’t Forget to Follow us on 👍 Social Networks, happy Splunking >😉