We are facing an abnormal issue where the number of requests increases to very high value for about 7 hours. Normally we are able to serve with 60 connections at a time, but open connections during these time reaches to as big as 400+ connections. I am also not able to find out any specific IP from which the request is coming. Can it be a probable DoS attack . What could be the issue ?

Any person who has previously faced such an issue or knows about it ?

What do your access logs say? Is there a particular page they are accessing? Is it even http traffic?

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