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kridsana's avatar
kridsana
Icon for Cirrocumulus rankCirrocumulus
Dec 26, 2012

How to clear Don't Fragment (DF) bit

there is some virtual server that have a problem that     packet segment lost when MTU = 1500     so i want to clear DF bit to fix this problem , and how to clear it?     than...
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Hamish's avatar
Hamish
Icon for Cirrocumulus rankCirrocumulus
Jan 05, 2013
Are you using 1500 Byte packet size? Or ping -s 1500 which will send 2x packets as it's specifying 1500Bytes of DATA in the ping... (WHich of course doesn't fit if your MTU is 1500).

 

 

However as WLB says above, perhaps you have Jumbo frames configured on one side of checkpoint and 1500 on the other (WHich would generate the WOULD FRAGMENT in response to tryiung to forward a packet > 1500Bytes [1514 including the MAC addresses and type] from a jumbo frame interface to an interface with a 1500Byte (Or smaller) MTU).

 

 

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