This was a more generic comment than what you seem to have understood. To borrow a 'trade' term, measure twice, cut once. Make sure that before you do something in the real world that it is the right thing. We all do things to our own systems that we would never consider doing on production systems because all it costs us is a little time if it goes bad. On the other hand that little bit of time is VERY expensive if it happens on mission critical systems or ones where there are a large number of users impacted.

Learning to use and administer your own Linux/Solaris is not the same as being able to deal with the types of issues that can on a large Unix system. As a really simple example a reboot on a pc will take a couple of minutes but a reboot on a large unix system can take a long time ( I have known fully populated SunFire 6900s take an hour or more to reboot )

For training, all the vendors have information about their education services on their websites, you can often find third parties that give adequate if not quite equivalent course.

The vendor websites will also have info on certifications.