Connecting to SQL Server from R which is Running on Remote UNIX Machine

We have a UNIX machine which includes R engine on it and installed SQL Server ODBC Driver 11. We need to connect R to SQL Server. SQL Server currently works on another machine, so we tried to connect R to SQL Server with the code below. library(RODBC) dbhandle Warning messages: 1: In odbcDriverConnect("driver=ODBC Driver 11 for > SQL Server;server=10.XXX.XX.XX:1663;") : > > [RODBC] ERROR: state HYT00, code 0, message [unixODBC][Microsoft][ODBC > Driver 11 for SQL Server]**Login timeout expired** 2: In > odbcDriverConnect("driver=ODBC Driver 11 for SQL > Server;server=10.XXX.XX.XX:1663;") : > > [RODBC] ERROR: state 08001, code 87, message > [unixODBC][Microsoft][ODBC Driver 11 for SQL Server]**A network-related > or instance-specific error has occurred while establishing a > connection to SQL Server.** Server is not found or not accessible. Check > if instance name is correct and if SQL Server is configured to allow > remote connections. For more information see SQL Server Books Online. > 3: In odbcDriverConnect("driver=ODBC Driver 11 for SQL > Server;server=10.XXX.XX.XX:1663;") : > > [RODBC] ERROR: state 08001, code 87, message > [unixODBC][Microsoft][ODBC Driver 11 for SQL Server]SQL Server Network > Interfaces: Connection string is not valid . 4: In > odbcDriverConnect("driver=ODBC Driver 11 for SQL > Server;server=10.XXX.XX.XX:1663;") : ODBC connection failed If I run telnet to SQL Server from UNIX machine, it works perfectly. I mean there is a healthy connection between these two machine. How can we connect R to SQL Server without using DSN?