IB_PROTOCOL environmental variable introduced in InterBase 7.5

By: Quinn Wildman

Abstract: IB_PROTOCOL allows you to specify the default InterBase server port to connect.

InterBase 7.5 introduces the capability to allow multiple InterBase servers to be run on the computer. This capability is provided by having each server run on a different port. Clients and Servers need entries in the services file indicating the label name and port. For example:

gds_db 3050/tcp #default InterBase port number
ib_var_a 3051/tcp #VAR A's InterBase port number

In order to access an InterBase 7.5 server running on any port other than 3050, the port must be specified in the connect string. For example:


If you do not specify a port, gds_db is assumed.

The IB_PROTOCOL environmental variable allows you to set the default port to a port other than gds_db. For example, if you set IB_PROTOCOL equal to ib_var_a, then the above connect string could be changed to:


Server Response from: ETNASC04