Atomicorp

Can I do anything about this warning?
The program yum-complete-transaction is NOT found.

Resolution: This is not an ASL error, you can read our unofficial advice here:
https://www.atomicorp.com/wiki/index.ph ... _remaining.
This tool is not supported by us. Contact your OS vendor for support.

My sysadmin say:

Please note that in a normal condition this shouldn't cause any issue on your OS. But since you have made a lot of changes on your OS. We are not guarantee that this will solve your problem.

Has anyone had any experience with this tool?
Is it safe to install and run it in an attempt to deal with the yum update warning?

Yup, it was added by redhat/fedora a few years ago. It is part of the overall system that allows you to (among other things) pause & resume upgrades. Im surprised your sysadmin didnt know about it, its a fairly significant part of the package management system. If you dont know where a component comes from you can use "yum provides /path/to/file" (wildcards accepted) to search.