Good morning everyone! I'm preparing to upgrade my RHEL 7.9 servers to RHEL 8.x, but my IT team prefers to do a clean reinstall instead. I'm worried that some of my configurations might get lost in the process. Can anyone recommend which commands or files I should use to save or export my various setups, such as kernel settings and network parameters? Thanks in advance!
5 Answers
From my experience, it's best to build a new machine and copy the necessary files over, like home directories and crontabs. Once everything's migrated, you can rename and re-IP the new server to match the old one, then do some testing. This way, if anything goes wrong, you have the old server to fall back on.
If you haven't already, this is a great opportunity to automate your setup. Stop treating servers like pets and use tools to document and replicate your configurations automatically.
Try using `$ sudo sos report`. This will create a tar file containing a comprehensive log of all your server configurations, including crontabs and diagnostic outputs. It’s really helpful, but if it seems overwhelming, tools like sos-vault can help analyze it.
It really depends on what's installed. A good approach is to automate with an Ansible playbook. Now would be the right time to create documentation or any scripts you might need for the server configuration.
You'll want to back up everything in `/etc` and below. Also, don't forget to export your RPM list and any services that are set to start on boot. It might be useful to get a list of your crontabs as well, especially if you have any custom scripts.
/var/spool/cron is where you'll find the crontabs.
Thanks for the tips!