I had installed
BIND service on my centOS 8 server with
recursion yes; configuration. I noticed a very large traffic (~ 8 GB) is being sent from my server every hour and I could not detect what is the source of this traffic. then I changed the named configuration and disabled recursion:
after disabling recursion and measuring traffic I can see the send traffic has dropped dramatically to below 200 MB. now my question is that how this recursion can cause such large send traffic?!