{ CommLinks | LINKS }={ [ SharedMemory | ShMem ] | ALL | [ TCPIP | TCP ] } [, ... ] string

The CommLinks (LINKS) connection parameter can be used for connections to a network database server and is optional for connections to a personal database server.

CommLinks (LINKS) connection parameter values are case insensitive, and include:

SharedMemory

If you do not specify a Host connection parameter or a CommLinks (LINKS) connection parameter, the client searches for a database server on the current computer only, and only using a shared memory connection. This is the default behavior, and is equivalent to CommLinks=ShMem. The shared memory protocol is the fastest communication link between a client and database server running on the same computer, as is typical for applications connecting to a personal database server.

For information about securing shared memory connections on Unix, see Security tips.

If you specify both TCPIP and SharedMemory or CommLinks=ALL, then shared memory is attempted first, followed by TCP/IP if the database server cannot be found over shared memory. For example, in the following connection string, shared memory is attempted first:

"UID=DBA;PWD=sql;Server=demo;DBN=demo;LINKS=TCPIP,SHMEM"

A personal database server is not started automatically if the Host connection parameter is specified or the CommLinks (LINKS) parameter includes TCP/IP.

The TCP/IP communication protocol is enabled on the database server using the -x option.

• Host connection parameter
• Network protocol options
• Communication protocols
• -x dbeng12/dbsrv12 server option
• Connection parameters and connection strings
• Caching database server address information in sasrv.ini for faster connections
• CommLink connection property

The following connection string fragment attempts to connect to the database server named demo running on the current subnet:

CommLinks=tcpip;Server=demo;UID=DBA;PWD=sql;

The following connection string fragment attempts to connect to the database server named demo. It first attempts to connect over shared memory. If the database server cannot be located using the shared memory, it attempts to connect using TCP/IP.

CommLinks=tcpip,shmem;Server=demo;UID=DBA;PWD=sql

The following connection string attempts to connect to the server named demo running on the host named kangaroo.

CommLinks=tcpip(HOST=kangaroo);Server=demo;UID=DBA;PWD=sql

Alternatively, you could use the Host connection parameter to connect to the server named demo running on the host named kangaroo.

Host=kangaroo;Server=demo;UID=DBA;PWD=sql