While installing OpenSUSE LEAP 15.1 I tried to assign a static IP so that I will have LESS to do after the installation is done. Good advice is to NOT to do that. I did, and the system did not tell med that there was something wrong with the configuration(could not access the internet). What happens is this:

 - You think everything is all right until there are packages that need to be downloaded or updated, and not from the local medium.

I did that mistake twice, .

First time: when I wanted to install a "Transaction Server"...I wasn't sure what it was so I discarded the whole thing when I did not have anything to work with after the installation.
Second time: Installed a "Server", and saw and was aware that it was not downloading the "packages" it wanted from the an internet repository.

Good advice: Change to a static IP after the installation. Use the default internet-settings while installing. Actually: Just get the basic installation done and download/configure your server after the basic installation is done. It will save you alot of time if you only have basic knowledge of Linux/OpenSuSE like me.

Happy installing!