Packet Drops

[Anuj Singhi]

I am getting below message on Cisco 4507 R+E

%C4K_L2MAN-6-INVALIDSOURCEADDRESSPACKET: (Suppressed 2093 times)Packet received with invalid source MAC address (00:00:00:00:00:00) on port Po10 in vlan 48

from various ports and vlans. Because of this users connected to this switch are expereincing intermittent slowness. Can anybody suggest any solution for it.

[Charles Hill]

CSCto67828

4500 - drop invalid Mac address

i believe you are hitting bug CSCto67828

Workaround:This message is informational and does not indicate any issue with the 4500. The 4500 is performing a security function and alerting the network engineer to the fact that invalid source ip addresses are being used on the network.

This bug was opened to have the 4500 drop these invalid packets in hardware instead of software. It is an enhancement to the software to allow the 4500 to drop these packets in hardware.

The only way to isolate the source of this issue (invalid source mac address) is to find out the faulty NIC card that generates this error message or track down the device generating the invalid packet.

Please be aware that it may be an ASA generating these packets or a faulty NIC card per

See bug for known fixed releases.

Hope this helps

Please rate helpful posts

thanks

[Anuj Singhi]

But I am receiving this message from lots of ports and vlan and since its 00:00:00:00:00, its not possible to trace it. Is there any workaround from stopping these message or anyway to find the source? Its eating my CPU.

[Charles Hill · Accepted solution]

Upgrade to a known fixed release.

not sure if what is listed under more info will help but you can try

More Info:

A static mac address table drop entry can now be created to drop all the packets in hardware with a source mac address of 0000.0000.0000 for a particular vlan by configuring "mac address-table static 0.0.0 vlan {vlan#} drop"

Hope this helps.