Incredibly high peak of traffic (Network In) on AWS [closed]
Solution 1:
This is clearly a bug in the software computing the traffic rate. You need to show the image to the vendor of the software, which produced the graph. That's the only way, you are going to get an answer as to what happened.
Probably some negative number showed up where a positive number was expected, and wrapped around to around 18EB. Use that erroneous number in further calculations, and graphs like this happen.
You can not expect to find an explanation on the server itself, because there is no way this amount of traffic could have happened on the server.