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Support for MTU > 1460 bytes

If UDP packet's exceed the size of 1460 bytes, they seem to get fragmented by the network and cannot be reassembled accordingly on GCE instance.

Is it planned to increase the MTU or is there a known workaround how reassembly can be done accordingly?

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    Justin Beckwith shared this idea  ·   ·  Flag idea as inappropriate…  ·  Admin →

    5 comments

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      • AdminPaul Nash (Product Manager, GCE, Google) commented  ·   ·  Flag as inappropriate

        The 1460 MTU is configured due to additional header space required inside Google's network. It is a difficult thing to change, but something that we're looking at.

        Note that unfortunately due to the complex nature of software and network topologies where this sometimes becomes a problem, we likely won't be able to diagnose or debug individual use cases in this forum.

      • a.varani@opengate.biz commented  ·   ·  Flag as inappropriate

        Default client and network mtu is 1500/1492, fragmentation cause also a very bad experience in using ssh client.

        But why 1460?

      • AdminJustin Beckwith (Product Manager, Google) commented  ·   ·  Flag as inappropriate

        If UDP packet's exceed the size of 1460 bytes, they seem to get fragmented by the network and cannot be reassembled accordingly on GCE instance.

        Is it planned to increase the MTU or is there a known workaround how reassembly can be done accordingly?

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