How can you mitigate fragmentation issues between endpoints separated by a GRE tunnel?

2 thoughts on “How can you mitigate fragmentation issues between endpoints separated by a GRE tunnel?”

1. https://www.cisco.com/c/en/us/support/docs/ip/generic-routing-encapsulation-gre/25885-pmtud-ipfrag.html

   Answer is PMTU

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2. A

   https://www.cisco.com/c/en/us/support/docs/ip/generic-routing-encapsulation-gre/25885-pmtud-ipfrag.html

   What is PMTUD?
   TCP MSS as described earlier takes care of fragmentation at the two endpoints of a TCP connection, but it does not handle the case where there is a smaller MTU link in the middle between these two endpoints. PMTUD was developed in order to avoid fragmentation in the path between the endpoints. It is used to dynamically determine the lowest MTU along the path from a packet’s source to its destination

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