Reverse lookup by ip address

When the maximum capacity is reached a random item is evicted. Default value is 1m. If there are multiple servers, the resolver queries them in the order listed.

Reverse IP Lookup

On Windows you must always supply at least one nameserver. This is timeout for each DNS request so if you have 2 nameservers then the total timeout will be 2 times this value.

Default value is ms. Next, we want to verify that the domain name matches the IP addressed used in step 1. To do this, we perform a forward DNS lookup for the returned domain name, again using the host command:.

And so the circle is now complete: from IP address to domain name, and then from domain name back to IP address. Otherwise, if either IP address or hostname does not match, the identity is not confirmed, and should be investigated further, if necessary. Say we want to verify Google reporting an IP address of We first run host on the IP:. Great question!

What is reverse DNS (rDNS)?

If one were to database the passing IP-Addresses in a quick-lookup table, then one could accept these vetted IP-Addresses as genuine. Email Address Remember me.

Set Reverse DNS and PTR Records - Stop Mails From being Spammed

Password Forgot your password? Enter a host name or an IP address:. Email Share.