Use dbisql to test the connection to the database.
Use dbisql -c connection-string. For example, to access the cache on the data tier installed in a cluster environment, use:
dbisql -c "dbn=default;uid=dba;pwd=sql;links=tcpip(DoBroadcast=NO;VerifyServerName=NO;host=localhost;port=5200)"
A text entry window for SQL commands indicates that the connection string is valid; you can exit the program and use the connection string in all required command line utilities. A window that prompts for additional connection parameters indicates that the connection string is invalid. Review the syntax and try again.