Tasks servers will sometimes drop all connections or not ever allow any connections. The error logs have a "Failed to call TS method 'RegisterClient'" error 10+ minutes after the atrshost.exe has been restarted.
Date: 3/5/2014 1:01:49 PM
Tick Count: 329921756
Host Name: SiteServer
Process: w3wp (10928)
Description: Failed to call TS method 'RegisterClient'. This is expected while
AtrsHost service is not yet started. Exception:
System.ServiceModel.EndpointNotFoundException: There was no endpoint listening
at net.pipe://localhost/rss/ClientTaskServer that could accept the message.
This is often caused by an incorrect address or SOAP action. See
InnerException, if present, for more details. ---> System.IO.PipeException: The
pipe endpoint 'net.pipe://localhost/rss/ClientTaskServer' could not be found on
your local machine.
This is a known issue that occurs when package server refresh happens.
This issue is scheduled to be addressed in 7.5 sp1.
The other possible work around to this issue is to bring up a different site server and spread out the client load.