I recently upgraded my .net 4.7.2 solution from Teradata.Net.Data.Provider 15.11.01 to Teradata.Client.Provider 16.20.1. Now I get a lot of  timeout connection errors. Out of 100, I will get it 13 timeouts. If I downgrade to 15.11.01 then all goes well and I am able to connect 100 out of 100.
I've been running on 15.11.01 for the past year generating ~ 1K + connections per day without ever getting one connection timeout error, but since I ported to 16.20.1 I am getting tons of errors.
I tried on 4 hosts including 2 servers, across various networks. I also tried setting the connection timeout to 90 seconds with no avail.
I tried setting connection timeout property to 0 with Connection Timeout=0; in the connection string, however it is still timing out after roughly what it seems 8-10 seconds. Even if I set it to 6000 seconds, it will be ok for a few connections and then suddenly it waits for a connection for 10 seconds so and then I get exception.