What happens to netfilter during end-of-day?

Hi,

I have a netfilter daemon that makes a looping call to mnl_socket_recvfrom() 
and quickly examines packet headers. It only stops when it's rebooted. However, 
almost every day it receives an ENOBUFS error, just once, around 4 AM, while 
running cron.daily.

I haven't found any useful logs from around the same time that explain what's 
happening. Does anyone have more information?


TIA
Ale
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