Large ping and network hang on Windows Server 2012 R2 server?

Question

Computer networks

The enterprise has an HP proliant server running Windows Server 2012 R2, AD+DNS+DHCP, and a file server.
Recently, from time to time, the server on the network freezes, the ping is unstable, it increases to 2000 ms, because of this, DNS and access to files over the network do not work correctly. Third-party programs and services are not running on the server, restarting the server does not help. Where and how can I find the source of the problem?

Answer 1

I had a similar experience with the freebsd gateway (it was on the internal interface that there was a high ping, and it was on the server, between other machines, the standard ping <= 1 ms). A kind of internal DDoS. Try to see with tcpdump or wireshark what is coming from where.

Answer 2

If there are no peak loads on the server, then first you need to eliminate the problem in the connection (cables, switches, connectors, etc.)