To configure A10 Networks Thunder to work with FastNetMon you need to apply following changes on A10 Networks side:
netflow monitor fnm protocol v10 record nat44 destination 10.0.0.100 2055 flow-timeout 1 resend-template timeout 60 source-address ip 10.0.0.1 !
Unfortunately, flow timeout uses minutes and 60 seconds it the best flow timeout we can get.
And specify average calculation time value:
sudo fcli set main average_calculation_time 60 sudo fcli commit