Open DNS check for a domain

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Open DNS check
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dig domain @ip

for example
dig facebook.com @8.8.8.8


8.8.8.8 -- static IP of google.com

facebook.com not hosted on 8.8.8.8 but still the ip replies to the query since the name server recursion is enabled.

If enabled and allow query then that ip has open  dns and allow only selected range of ip's

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