Unicast flooding

[S891]

I am seeing a strange issue on my network and I suspect that it could be uncast flooding. We have a Server that is being used for imaging of machines. The problem is that the traffic is appearing on access switches where there is no client and it is bringing the performance down for siwtches with low speed uplink (1G). 

The Server is located in data center and client machines are located in 3 Access Wiring closets but the same traffic is flooded to all access switches. A traffic capture indictes the packet type is NBSS (NetBIOS Session Service) Continuation Message. I am not sure why it is being flooded to all the network. Packet capture on an access switch which does not have any client showed that there are packets with source and destination address that does not need to be traversing this switch.

any suggestion would be helpful. 

[Reza Sharifi]

Try testing it by adding :

switchport block unicast

to a few ports and test again.

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst6500/ios/12-2SX/configuration/guide/book/blocking.html

HTH

[paul driver]

Hello

Just to add to reza's comments

You can also look into apply storm control to the access ports

int x/x
storm control unicast level x.x
storm control multiicast level x.x
storm control broadcast level x.x

res
Paul