Don't upgrade a server if it is working good 😒 seriously people?

Don't upgrade(or fiddle with in any way) servers that are running. Start a new server with the changes you want, verify that everything works properly, swap out the old.

The thing is not having a test server, they told me to NEVER upgrade the master server nevertheless the test one is working good upgraded

Is hard to tell need more context

I'm IT at my job, but my boss trust in anyone and a while ago someone's tell him that upgrades are not necessary cuz if everything is working, why upgrade?

Have to tell that my boss learned computing with floppy disk of 5 1/4 and since he graduated never again studied computing, also he doesn't known to code, or format a PC...

I have time trying to convince him to understand that is important upgrade because of security and stuff but still don't trust me...

Security updates are important.

The server use configuration management or somebody did a manual installation ?