I am trying to figure out is the possibility of Deploying Existing ASP.Net/C# 3.5 SP1 Website to Linux Server with Mono Runtime. Is it really safe for live web sites? Interested in this because of cost cutting.
If you have tested the application, and the .NET features that you use work...then go for it.
There are plenty of production/open-source applications that are built on top of Mono. The runtime is definitely stable enough to run on top of.
Look at this list from the mono project (Companies using Mono) and make your own mind up.
Should you use it? That depends on what features you need and whether they are supported.
I believe it is quite mature. For instance, FogCreek is using Mono to run FogBugz 7 on UNIX servers.
Mono itself is matured to run production websites (I would say that one of the best examples of this is Orions Belt ) however you can have certain issues with your existing web application during deployment. For example DbLinq (Linq to sql implementation in mono) is in preview release now and it is not recommended for production usage so it depends on technologies you are using and if they are supported.