Why do SFTP sessions remain open after job is done?

Introduction:

This knowledge base article provides details regarding the functionality of the MFT application and OS regarding SFTP sessions while using push and pull jobs.

Details:

When doing SFTP push or pull jobs, there are TCP connections being opened with multiple states. While the job is running the connection is established (expected):

C:\Users\Administrator>netstat -an | findstr :22

TCP 10.30.192.190:52699 10.30.192.192:22 ESTABLISHED

When the job is finished the connection is in pending:

C:\Users\Administrator>netstat -an | findstr :22

TCP 10.30.192.190:52699 10.30.192.192:22 TIME_WAIT

This stage runs for around 2 mins then it stops the connection.

“TIME_WAIT” status is normal, as OS holds sockets opened for 2 mins by default, in-case a frequent reuse would be necessary to avoid costly creation. The connection is canceled in that state.