Null service names

Some DB-Library™ versions do not provide a remote server name for service routing, so requests from these DB-Library applications contain null service names. If you run multiple services with a single server, you must use service name redirection to connect such clients. In particular, consider:

Microsoft DB-Library requests contain null service names, because the specified service name is not passed to Open Server in the internal login record. You must use service name redirection to connect such clients.
Sybase Open Client DB-Library and earlier do not provide a remote server name. You must use service name redirection to connect such clients.
Sybase Open Client DB-Library and later provide the server name. With these clients, you can use direct routing or service name redirection.

If the requested_service name is a null or empty string, the service name redirection file line for routing that service must begin with a tab character. Table 6-1 shows an example of a service name redirection file with a null requested_service name.

**Table 6-1: Sample of null service name format**
requested_service	user_id	application_name	assigned_service
<tab>	Jane	db-lib	svc_db2