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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
Dec 27, 2012
PMTU discovery SHOULD work though most networks. If they're installed and maintained by professionals who know what they're doing, and care about not being woken by callouts about strange issues with established connections timing out and dropping.

 

 

With IPv6 PMTU discovery is pretty much mandatory, or you set your remote MTU to 1280 (?) which is the minimum MTU for IPv6.

 

 

A better fix would be to find out where the ICMP host unreachables are being dropped and fix it.

 

 

H