In other words I am trying to make the nexus 9k to fragment the packets on last hop.
I realize by default PMTUD is enabled, but even when disabling it, it makes no different after restarting connections.
What I see is when a message is routed to my application and its mtu is larger than its mtu, the packets are dropped by the nx9k with df-bit set and the icmp unreachable (fragmentation needed) is returned back to the client. So I am trying to see if the nx9k can clear df0-bit and perhaps fragment rather than drop. Is this possible?