Hello,
My Yahoo has been working OK.
Why do you think 204.71.200.72 is a Yahoo DNS server?
;; ADDITIONAL SECTION:
ns1.yahoo.com. 135214 IN A 68.180.131.16
ns2.yahoo.com. 46822 IN A 68.142.255.16
ns3.yahoo.com. 43393 IN A 121.101.152.99
ns4.yahoo.com. 114591 IN A 68.142.196.63
ns5.yahoo.com. 113082 IN A 119.160.247.124
ns6.yahoo.com. 39441 IN A 202.43.223.170
ns8.yahoo.com. 77690 IN A 202.165.104.22
Even if it is, it's not uncommon for DNS servers to block unnecessary ICMP traffic (ping, traceroute, etc)
Also, if there was a Yahoo DNS server that was down, your DNS resolver would/should know to query a different DNS server when looking up answers within the Yahoo DNS.
I hope this information helps. Please share if you have any more details.
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