Hi. I'd like to ask, after following youtube guide on how to determine optimized MTU and setting, I have this question below:

- Default Asus RT-AX55 MTU setting is 1492. When I ping google I get reply Packets needs to be fragmented and DF set.. So I start from 1500, slowly minus 10, until I discover my optimized value is 1464.

-After setting MTU to 1464, then I try the process again, and I get the same reply Packets needs to be fragmented and DF set.
Sent 4, Received 0, Lost 4

Am I doing something wrong? It seems so easy to test and find the optimized value but why after setting to optimized value, I get the not optimized readings?

Also, do I leave MRU alone or change MRU to the same value as MTU?