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New Member

%I82543-3-TOOBIG: GigabitEthernet0/0, packet too big (4139)


I keep on getting the following message in my 7204VXR's log:

%I82543-3-TOOBIG: GigabitEthernet0/0, packet too big (4139), from 0100.0c00.0000

I am running DLSw on the 7204 and it is peering to a 7513 with a CIP2 installed.

Dean Young

  • Other Network Infrastructure Subjects

Re: %I82543-3-TOOBIG: GigabitEthernet0/0, packet too big (4139)

You are recieving a packet from 0100.0c00.0000 that has a packet size larger than the MTU of the Gig interface.

Change the MTU size is your best bet, The GEPA supports MTU size up to 4470 bytes in full-duplex mode for point-to-point links.

New Member

Re: %I82543-3-TOOBIG: GigabitEthernet0/0, packet too big (4139)

Thanks. What bothers me here is that I have 4 x 7204 routers and they all get the same message from the same mac address. I searched my network for this mac, but could not find it.

Any help?

Re: %I82543-3-TOOBIG: GigabitEthernet0/0, packet too big (4139)

The MAC 0100.0c00.0000 is M/cast belonging to ISL, so my guess is you got this connected to a switch and not sure if you are running VLAN's to the gig interface, if you are not then turn off trunking on the switch port.

Cheers Boet..:)

New Member

Re: %I82543-3-TOOBIG: GigabitEthernet0/0, packet too big (4139)

Thanks. I am running DLSw Ethernet redundancy on the 7204 and I have ISL running between the 7204 and the CAT6509. I am also running VLAN's on the sub interface of the 7204.


Re: %I82543-3-TOOBIG: GigabitEthernet0/0, packet too big (4139)

Then i would suggest up'ing your MTU.. as long as you have enough shared MEM you will be okay, i would suggest changing this in a quite period as IOS will re-run the carve algo and on a busy box it cadn cause a little upset.