All node managers running into unexpected exits or process status bad

[#1]

I have 9 node managers in my cluster and all of them are randomly exiting. I can see that suddenly java threads are pretty high which was not the case so far.

What could be the reason that all node managers randomly exit? Reiterating : not specific to one or two node managers.

[#2]

Hey @Simran kaur.
Could you post your yarn node managers logs errors?
If its not showing any WARN|ERR messages, you can try to raise the log's level to DEBUG.
BTW, how much Heap Size you've set?