FT of 50.000-100.000 files or more freezes in status "Connecting" 

This happens in 1-out-of-2 to 3 transfers.

In rare cases the files are transferred but the agent hangs.

This behavior has been observed on Unix Agents only

Solution: 
Update to a fix version listed below or a newer version if available.

Fix version:
Component(s): Agent

Automation Engine v12.1.5 2019-05-20
Automation Engine v12.2.3 2019-06-04
Automation Engine v12.3.0 2018-06-28
Automation Engine v12.1.4HF1- Available
Automation Engine v12.2.2HF2 - Available