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VXLAN with large MTU
We are having a weird issue with capturing traffic with VXLAN. The issue is that for some requests we didnt receive response body. The setup goes as follow: an AWS ALB forward traffic to an application vm (Apache), the ALB port is mirrored to a goreplay in the same subnet.
After some investigation we noticed that both application VM and GOR VM have large MTU (9000) and lowering the application MTU lower than ~1500 fix the issue.
We cannot keep this low mtu in our environment, so this solution is not really viable for us.
This issue might be related to #1096 .
Yes when we have developed this feature we have fixed the MTU. I'm thinking we can add parameter to customize and manage the jumbo frames. Or I don't know yet detect the MTU.
const VxLanPacketSize = 1526 //vxlan 8 B + ethernet II 1518 B