Connecting to MSSQL server using sqlcmd and odbc driver on RHEL 6 fails

After reading this thread: https://github.com/Microsoft/msphpsql/issues/190

I had to find out another portnumber SQL Server was listening on by executing

USE MASTER 
GO 
xp_readerrorlog 0, 1, N'Server is listening on' 
GO

Result

2018-04-12 03:19:57.830 Server       Server is listening on [ 'any' <ipv6> 49155].                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
2018-04-12 03:19:57.830 Server       Server is listening on [ 'any' <ipv4> 49155]. 

add a Rule for the Windows Firewall on SQL Server host: - enabling specific Port 49155 (I think this can vary)

Then this command succeeded on my Ubuntu machine:

sqlcmd -Smyhost,49155 -U sa -P sa_pwd -d mydb -Q "select @@servername"