ā12-08-2015 03:52 AM - edited ā03-08-2019 03:00 AM
As the Pic below, It says that C1 can send the packet to C2, and the SW's port 2 would not do the fragment, but I still don't get it.
I thought MTU liked the size of the pipe, if set the MTU = 1514, it means that the pipe size is 1514, every frame bigger than 1514 should not pass through.
And would the layer 2 switch check the FCS field in layer 2 frame ?
ā12-08-2015 05:03 AM
Disclaimer
The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
Liability Disclaimer
In no event shall Author be liable for any damages wha2tsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
Posting
Yes, the picture says that, but that doesn't guarantee the picture is correct.
What it shows, if the (Juniper?) EX4200 supports, is poor practice, i.e. having (it appears) two ports on the same switch with the same VLAN with different MTUs.
I would expect a switch to drop a too large MTU frame on ingress or (L2) egress, but perhaps an EX4200 has some "quirk" that it doesn't enforce port MTU, for (L2) egress, if the frame is already within the VLAN.
ā12-08-2015 05:45 AM
Hi Joseph,
I just want to know how does the switch process the packet when the packet is bigger than the MTU of the switch's interface.
From this Pic, it appears that the switch would forward the frame and don't check the MTU in the egree interface.
Discover and save your favorite ideas. Come back to expert answers, step-by-step guides, recent topics, and more.
New here? Get started with these tips. How to use Community New member guide