How to update my ELK server?

I am almost finished building my ELK server which i found exiting to do. I have pushed already 12 logs to my ELK server and have almost 5GB of indexes. All runs fine and i am now exploring how to proper use this neat tool so i can convince my old server administrator to use my ELK server instead of his old grep text based server he ever build (which works fine also).

So i found a webinar movie on this website and when i was following it, he mentioned a few times to keep ELK up to date. And not only that, also Java version. So, of course, i checked my Java version and found out i have 1.7.0_91 which is not recommended.

Also he mentioned to update Elasticsearch on a regular basis. But here comes the do i safely update my ELK incl. Java?

I installed all packages trough RPM (when possible) and not trough a repository. So, to be honest, i am afraid i will break things if i try to update my packages.

Is there any convenient way to keep my server up to date without breaking things?

There shouldn't be anything scary about updating software via RPM. I don't know what you're worried about. Just make sure you read the release notes. They'll contain information about breaking changes.

I agree with Magnus on reading up on the breaking changes.
Most of the time when upgrading from something there will be changes which will make the update difficult.

I'd suggest making a snapshot/backup of your ELK server as it is now.

Also I suggest reading this as it has some pretty game breaking points of interest