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New Member

invalid packet length error in logs

For over a week now I’ve been getting the following error in my log once a minute:

 

Invalid packet (too large) length=17247

 

I’ve seen it stop for maybe an few hours a couple times but otherwise it’s constant. Anyone know how to track down who or what is sending this invalid packet?

Thanks

2 REPLIES

Hi,your router will drop the

Hi,

your router will drop the over sized packet if the DF flag is set.  However, it will return a message to the originating device showing packet oversize.
You can try setting the router logging to debug and verbose.  This should return the originating IP.  One other thing that you can do is take a close look at any devices  that you have setup.

Additionally, you can try changing the MTU on the router but this could result in performance 
degradation.  Alternatively, if you can identify the originating device, you can try changing
 the MTU there as well.

 

HTH 

Houtan

New Member

I'm actually on a switch

I'm actually on a switch (3850), not a router.

Do you know what debug command to use? Looking at the debug options there's so many and I have on clue which one to use.

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