Sort of Broadcast on 6509 (but its unicast)

[ahmad82pkn]

Hi,

i have a strange issue from last 3 days, i can see 10Mbps out on every connected port of switch and receive is normal as it use to be that is 500Kbps to 2Mbps, for some port receive if 500Kbps etc.

what i dont understand that why all ports are trnasmitting 10Mbps at sudden.

i sniffed one of the port and found below capture in PCAP.

Destination IP is unicast , NLB luster Server IP. but dont know why traffic going to all other ports.

any suggestion?    

FYI destination mac is learned form one port only, but traffic going to other ports as well for some odd reason.

attached is pcap snapshot. any hint would be appreciated:)

[Pronoy Dasgupta · Accepted solution]

Hello Ahmad,

Do you have servers which are configured in multicast mode NLB? If yes, then the switch needs to be configured for the same, otherwise by default whatever traffic the switch received, which is destined for the NLB IP, will be broadcast out of other interfaces in the same vlan.

Reference link:

http://www.cisco.com/en/US/customer/products/hw/switches/ps708/products_configuration_example09186a0080a07203.shtml

HTH

PD

[ahmad82pkn]

You are right, i found the same document, i guess thats the issue, i have reported it to concern NLB team so that we can fix it together, thanx for the help.