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New Member

Invalid Mac-address.

Dear NetPro,

Does anyone can guide me what to do now ?

your reply will be highly appreciated.

2006-03-05 16:31:53 Local7.Info xxx.xxx.xxx.xxx 417: Mar 5 16:40:08.885: %C4K_L2MAN-6-INVALIDSOURCEADDRESSPACKET: Packet received with invalid source MAC address (45:00:00:3C:A6:D4) on port Fax/xx in vlan xxx

Regards,

Jack

  • Other Network Infrastructure Subjects
8 REPLIES
Purple

Re: Invalid Mac-address.

Hi Jack,

You get that error when a packet with a source address that is a multicast address is received on an interface. It is illegal to use a multicast address as a source address in packets.

You will need to check what devices are attached to the port in question in order to determine which of the devices is sending these packets.

Hope that helps - pls rate the post if it does.

Paresh

New Member

Re: Invalid Mac-address.

Hi Paresh,

i've checked, this switcport is connected to the server. i just curious about, would it be the application caused the multicast (invalid mac-address) ? normally in what situation and environment will occurred ?

what can i do now ? disable the switch port ? change the NIC ? or etc ... ?

Regards,

Jack

Purple

Re: Invalid Mac-address.

Hi Jack,

How many of these packets are you getting ? If it's a small number, I would not worry about it too much.

However, if the number is significant you might not need to isolate it to the application on the server. In general, the IP to MAC conversion is done by the ethernet stack. But it may be an issue with the NIC or a mis-behaving application. It is not always easy to find out which application is causing it. You could do a couple of things (but none of those may solve the problem):

- replace the NIC

- shut down one app on the server at a time and see if the packets stop

Hope that helps - pls rate the post if it does.

Paresh

New Member

Re: Invalid Mac-address.

Hi Paresh,

thanks for reply, i have a question, from your message, you have mentioned about the number, what is that mean for the number getting small or significant ?

Thanks.

regards,

Jack

Purple

Re: Invalid Mac-address.

That should have read 'number of packets'... basically, I was asking how significant the problem was ...

Paresh

New Member

Re: Invalid Mac-address.

Hi Paresh,

is that what u mean ?

2006-03-05 16:31:53 Local7.Info xxx.xxx.xxx.xxx 417:

"417" ??

Regards,

Jack

Re: Invalid Mac-address.

Basically, what he meant is how often is the switch logging the message? if it's logging every second that's a "significant" number that that server is generating, if the message is being logged once a day then the server is generating the invalid packet at a "very small" amount. The question is why it's generating that packet? as the message indicated this is an invalid packet.

Bronze

Re: Invalid Mac-address.

Just a suggestion, you could use an open source packet analyzer like etheral running on the server to determine when it was generated.

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