I always felt Roon client shouldn’t even have the server option. From day one I used Roon as RoonServer and connected to the server with Roon (client). I never though of just using Roon. Such a foreign concept to me.
EVERYONE should run RoonServer separate from the client.
(That my opinion… and it’s the best one!) 
I use “just Roon” on my Dell XPS frequently when away from home. It works great with iPhone/iPad Verizon hotspot, WIFI RPI4 and USB to Mojo 2.
so you saying you install and place “Roon core” in your dell computer, connect it wired to your router, leave the power mode to never sleep, leave that computer on 24/7 and use remote to control music in the house and use ARC on. phone when out and about town and earth?
according to Marin, he says Roon server will do. is that the same?
I installed it and open the app, nothing happens. I am assume I must download the “Roon core” first and then open the Roon server?
No, I did not say that at all. At home I have a Roon Nucleus that runs Roon core 24/7 and connects to my router via ethernet. The router has port forwarding set up for Roon ARC support.
When away from home, I use my Dell XPS 15 laptop running Roon software to have Roon available at my hotel or relatives homes, etc.
Until recently, I had one Roon license and had to unauthorize my Nucleus core when I wanted to use my Dell core. This meant Roon ARC was no longer available. This month I bought a second Roon lifetime license so I can keep my Nucleus authorized while also authorizing my Dell. This keeps Roon ARC working.
hey Jim, thanks for your help. I am sorry. I mean that is what I think you were trying to say. but no, it is not.
I don’t have a Roon Nucleus. I just want to have my OLD MacBook running 24/7 and wired connected to the internet. I want that OLD MacBook to be the “Roon core” with all my music attach with the USB drive. And be able to use the ARC app on my phone when I am not at home.
I just want the “Roon core” to be on 24/7.
That is my main goal since I am a lifetime member now of Roon.
any suggestion?
Mac mini for me (no monitor, just the Roon Server installed)
yes, yes and yes and yes…
MacBook? that is really old I do not think that can run the core. I think you need at least Catalina and my last MacBook was running leopard (I did wipe out and install volumio and now works fine as an end point)
I was wrong:
When was the last MacBook made?
June 5, 2017
Roon Server does not have the user interface component of Roon - it runs the Roon Core component in the background. You access the Core via a Roon client or Roon Remote.
You can do that, not a problem. If you think you will ever want to take the old Macbook with you somewhere to have Roon at that other location, you could install the full Roon software package. Otherwise, just install the Roon server software on that old Macbook. In that case, you will use your phone, tablet, or another computer as the Roon client to control Roon on the old Macbook.
Roon Server software is without GUI, so you’ll not “see” anything.
Install full Roon to “see” and control things, either on the same machine, or any other device.
Just be aware, that you’d need PC MAC or a large tablet to get all available configuration options, mobiles have limited functions.
You should really read up on the what and how with Roon in their knowledge base to get a better grasp of the concepts and wording, before trying to install and configure your setup while relying on convoluted and truncated user info.
Please come back with questions, if things still do not get clearer for you, because that’s what we’re here for, but basics are better covered by Roon’s documentation…
Good luck and have a great new year 
yeah, it’s 2012 MacBook Pro. LOL.
I was running the “core” on my new MacBook Pro 2021. and now I need to disconnect this one and install the “Roon server” on the OLD MacBook. I just installed Catalina on the OLD MacBook.
Catalina I think works for Roon Server. Install roon server on the old one, and use the MBP as remote. if you need to transfer the database search the help files or write here
Oh, so it is MacBook Pro. Sorry I was thinking Mackbook
my old MacBook is a white one, I think 2009 
…but earlier you said…
lol! I thought it was a 2015 until I opened it up from storage room. LOL. it’s a 2012. I had to update the MacOS and now I need to do the step you were telling me.
I will read up on it.
as of now, I just open the server and it ask me if I want to read the volume from my connect usb drive.
oh that is old. but mine is not too far from 2009, it’s a 2012. LOL
Strip as much as you can. Uncheck software updates, bluetooth, wifi, spotlight, notifications, Time Machine, uninstall unused apps
I am doing it now. so, the “core” and “Roon server” on the same OLD MacBook on for 24/7. Can I download the “core” onto my new MacBook and use it as a remote or is there another app to be download to be used on a MacBook to control the music? I know for iPad and phones, I could use ARC. How about if I want to control the music from my new MacBook?
A MacBook isn’t best used in this way. It’s not designed to be headless and run with screen folded down, they use the keyboard to help it release heat with it closed it cannot do this effectively and you run the risk of damaging it.