When you enable a connection, Integration Server initializes the connection pool, creating the number of connection instances you specified in the connection's Minimum Pool Size field. Whenever an HL7 Module service needs a connection, Integration Server provides a connection from the pool. If no connections are available in the pool, and the maximum pool size has not been reached, the server configures one or more new connections (according to the number specified in Pool Increment Size) and adds them to the connection pool. If the pool is full (as specified in Maximum Pool Size), the requesting service will wait for the Integration Server to obtain a connection, up to the length of time specified in the Block Timeout field, until a connection becomes available. Periodically, Integration Server inspects the pool and removes inactive connections that have exceeded the expiration period that you specified in Expire Timeout.

If the connection pool initialization fails (due to a network connection failure or some other type of exception), you can enable the system to retry the initialization any number of times, at specified intervals.

For information about configuring connections, see MLLP Connections.