It seems that allot of new users come here with allot of common issues that are not “In Your face documented” which can be prevented before you even start using Roon.
So I wanted to see if we can put something together and all chime in and have it around for new comers to benefit…
New to Roon? Welcome! 
So you want to install Roon? Want a bit more explanation on how Roon architecture comes all together and how it all talks to each other?
Go here: How Roon Works and Roon Architecture
here:
https://community.roonlabs.com/t/whats-the-difference-raat-vs-airplay/6891/5?u=tech_whisky_lab
and here:
If you are here is because you allready exhausted all of the amazing content @: Roon Support Page 
First thing to know is Jumbo frames are a big no no!
Allot of today’s NAS come with this enable and they want you to enable it on your network for performance purposes.
Roon says no! 
A good description, detail, and advice, of good network topology requirements for a proper experience with Roon can be found here:
With that said if you have WiFi in mind (Most of us do) the same Law applies, WiFi can be very sketchy specially when you play with Raspberry Pi’s and the likes… The math is simple HiFi Audio = High bandwidth. Quality Wireless/Latency is essential to a HiFi Audio environment.
Second: If you are thinking of using the Roon GUI, in general you will need a good graphics card to operate properly, Most GUI issues are related to low rendering capabilities and low memory.
Third: Tidal, SO now you found this awesome service that streams lossless and you love it! But you found that cuts in and out and the service is unstable and you just want to hit your roon server with a baseball bat! Wait, Don’t… Just like anything, Tidal requires a stable internet connection with good bandwidth, As per their FAQ:
Tidal can eat as much as 4.8Gb of data in one given day. Take that in account.
Try to first see if you have any ISP issues, Do a bandwidth test and see if things look ok…
Still having issues with Tidal or Tidal logins? IE: Login failures, unable to reach tidal, etc…
Restart your Core Service. For the most part restarting your core solves this issues.
Fourth: So now you fall in love all over again with your HiFi System but found that you are limited to lower resolution and would like to know what people use out there with Roon as their DAC/AMP combo… Look no further and go here:
Tips & Tricks
One of the main issues surrounding Roon always end up been network related…
Before I give you some tips on this topic lets first understand that Roon Core is a very chatty application on your Network, As explain before it send Multicast packets across your network to communicate and discover your Devices/Endpoints… This can be tricky to troubleshoot when you have a congested network… Just imagine you are sitting on 5PM traffic (Rush hour) and a family in a car decides to come out and just start screaming… That’s Roon…
Now you understand that Roon can be chatty across your network and makes sense to apply a few tips…
Tip 1 When you have several endpoints across wireless and you are having issues, Fall back to basics. Connect your core straight to your Switch/Router and your endpoint as well… This eliminates any wireless issues and help us help you pin point if any wireless issue.
Tip 2 If you are hardwired and you are still encountering network issues, Once again… Fall back to basics… Start with the least past of resistance…
Try new network cable.
Try a spare switch
If you are straight in to the router try and add a switch in between and connect one endpoint at the time, test and see your results.
Remember The more complex your network is the more difficult it is for others to help you! Allways fall back to basics when troubleshooting.
Be ready to cooperate with the community and get ahead of the game by posting the following information when you need attention of The Roon Support Team:
Tip 3 Have a local Firewall? Please make sure you forward ports or “allow” incoming and outgoing communications of the following port described on this post:
Quick links
Want to move your Roon Core? Want to know what is the best way to migrate?
All this can be found @ the Roon Knowledge Base
Here is a quick link:
Want to know the Roon update model?
Go here: Roon Updates
Want to know how to update or if your server/endpoint did?
Go here: My Roon Version
Wonder what gets backed-up and how it works?
From one of our Mods @Carl
If anybody likes to add to this please post below! Lets polish the list and have a common ground for preliminary issues that for the most part are self inflicted.
I am open to take info out and correct as well, This is what communities are for, Help each other out!