I tried to communicate to you that it is even unclear which /etc/passwd and which /etc/shadow, because there can be many operating systems there and Grub still does not know which one you are going to boot!
To begin with Grub does not know where to find /etc/passwd (how could it?). but even when it could and there is multi-boot openSUSE 15.1 and Ubuntu and openSUSE 15.2 and Windows 10 and … on the system, which /etc/passwd (or equivalent) to choose?
And what is the talking about LDAP. That is a network protocol! Grub is not a full fledged operating system, it does not do anything with networking.
The short answer to your questions is of course: No.
But I tried to communicate how you can understand why it is “No” and that you can come to that conclusion yourself. Trying to help, but also to teach. Unix/Linux has a steep learning curve (specialy if one’s mind is blocked by Windows habits), but without hints to understand things it will be even steeper.
Thank you for trying to communicate/help/teach me with your inputs. I was seeking confirmation because I wanted to be sure I fully understood the context of all the suggestions thrown at me, especially since I am coming from Windows and relatively new to Linux (both of which I admitted at the beginning of my post). My mind is probably still “blocked with Windows habits” as you have pointed out. If I’m being honest, I am trying to “unblock” my mind since I have taken that step to move away from Windows to begin with, and a successful transition, in my opinion, would entail a deep understanding on how something works.
About the LDAP part, I keep mentioning that because, as I have mentioned, I’m trying to see if there’s a way to centralize password management in a manner similar to Active Directory. Or better yet, let’s use FreeIPA for comparison with the idea I’m trying to drive at because that’s Linux (care of Fedora), so I don’t look like I’m entirely still blocked by Windows habits. I haven’t found an equivalent to FreeIPA here in openSUSE, and what I have seen so far is that it was previously attempted to be made available in Leap/Tumbleweed but it appears to have been discontinued. In that case, given I’m starting to like openSUSE better than Fedora and Ubuntu, I decided to look into a setup that comes close to it by combining the separate parts that make up FreeIPA. So that’s how I arrived at LDAP, because that handles the directory server part.
Again, I thank you for trying to communicate/help/teach me with your inputs. That short, straightforward No pretty much answers the question running in my head. I’ll play around with the OS some more and just post another question if I run into something different.
I maybe a bit short and rather technical in my answers, reserving the small talk for other places.
And yes, it might realy be difficult to understand what the consequences are of things like multi-boot and what it realy means to have a multu-user, muti session operating system like Unix/Linux. It means that at many times you have to free yourself from the idea that this is a personal computer with only one user and only one session at the time.
Answers to questions are often better understood when you understand that there can be more operating systems (of very different signature) to boot from and the fact that there is only one on a particular system, is of no importance.
Same for users. There is never only one user defined on the system. You may know at least two (root and the user you created on installation), but there are more. Have a look in /etc/passwd, there are about 20 at least.
Same again for sessions. Always be aware of the fact that the operating system, system tools, system configurations, etc. must be and are accomodated for having more users (different or the same) at the same time loged in in the system, either through the CLI or the GUI. And yes, that has it’s drawbacks. It means e.g. that things like NetworkManager are in fact not Unix/Linux friendly because they allow a particular user that is loged in to mange the network. What about the others that may be loged in. Not something dfor you to solve, but something to contemplate about
It is a complete new world for many. But we are here to help you. Do not bother to asks things. No question is realy stupid. People might point you to documentation and when you show that you have tried to understand that documentation, but still have questions, they will be happy to help you with the details.
