A server with server class db2odbc is IBM DB2.
Sybase certifies the use of IBM's DB2 Connect version 5, with fix pack WR09044. Configure and test your ODBC configuration using the instructions for that product. SQL Anywhere has no specific requirements on configuration of DB2 data sources.
The following is an example of a CREATE EXISTING TABLE statement for a DB2 server with an ODBC data source named mydb2:
CREATE EXISTING TABLE ibmcol AT 'mydb2..sysibm.syscolumns'
Data type conversions: DB2