Microsoft has changed the way people interpret SQL server by going beyond the comfort level of windows operating systems. With SQL Server 207 release it is very easy to deploy SQL server on Linux Kernels. Deploying SQL Server on Linux helps to keep the exposure limited by providing the least surface area for exploits to hit the running service.
Microsoft efforts on this is based on the compatibility layer SQLPAL . This platform abstraction layer enables the subset of windows library required by SQL server to be also run on Linux server. Traditionally even on windows, a SQL server used to run its own libraries by having its own memory and thread management via layer called SQL operating system.
With the development of SQL server 2017 SQL operating system became part of SQLPAL and hence Linux native API’s could be called directly. While much is being set regarding the performance of SQL on windows compared to Linux in my opinion, SQL server performance on Linux is much higher than windows .
While a replication is not supported completely on linux distros, we expect things to change in near future.