Hi there, I have an unsolved issue regarding to my Concurrent Managers. They are often getting down

I have about 10 Concurrent Managers that created by myself for separating request purpose. They have been used for about 2 years more. Sometimes one of them down with status "Target Node/Queue unavailable" in a week / month frequency. And I just fixed it by restarting concurrent manager.

But now, may be 2 weeks ago until now it's getting worst. One or two or more concurrent managers down with status "Target Node/Queue unavailable" almost once a day even more than once everyday. It's really affecting the request queuing in my production EBS.

All I want to know is :

- What is the root cause of this ? why does the target node of the down conc.mgr gettting blank/null unexpectedly although it was started normally with the right target node and control code.