I had configured a DNS server.But when nslookup with the IP address of the DNS server.
It shows something like that"x.x.x.x.in-addr.arpa name=dns.domain.com".
But when i nslookup with the dns.domain.com output is ok.
Linux – DNS configuration doesn’t work
linux
Best Answer
The output of nslookup is to be expected.
When you look up an IP address for which a PTR record is set up, the result is that same IP address, with the octets printed in reverse order, ending with
in-addr.arpa
.Finally, you get the corresponding fully qualified domain name set in the PTR record.
If a PTR record is not set, you will get NXDOMAIN as a lookup result for that IP address.
Example of a result of a reverse lookup with a PTR record
I do a lookup of twitter.com
I now do a reverse lookup of the first result of my previous lookup.
Ok, so it turns out that the folks at twitter set up a PTR record for that IP address (note that the octets of the IP in the output are reversed, beginning with 10 and ending with 199) that points to r-199-59-148-10.twttr.com.
Example of a result of a reverse lookup without a PTR record
Let's do the same thing for this website, stackoverflow.com
The result is only one IP address, let's do a reverse lookup on that.
Again, the octets in the output have been reversed and appended with
.in-addr.arpa
. The result this time is not a domain name, but NXDOMAIN. No PTR record is set.