About MTU of NSX edge

[networlddsg]

Hello.

NSX Edge Interface has MTU setting place.

Is this correct in terms of the maximum MTU size when sending packets from NSX Edge?

If correct,

Is it correct in understanding below?

① Set the MTU size of the NSX Edge to 1500.

② MTU 9000 packet arrives at NSX Edge from guest OS

③ Communication routed by NSX Edge is fragmented and communicated to MTU 1500

[smitmartijn]

Hi,

You're half-right in the depiction. You would have to put the internal link on MTU 9000 and the external uplink of the Edge on MTU 1500. The Edge is indeed capable of fragmentation.

While I can't find documentation confirming this, I just tested the following scenario in my lab: VM with MTU 9000 -> Logical Switch -> Edge internal MTU 9000 -> Edge external MTU 1500 -> VLAN Portgroup MTU 1500 -> Web server with MTU 1500.

When I get a HTTP request with a body of a couple of MBs, there were frames coming into the Edge of 9000 bytes and leaving it of 1500 bytes.