About
A reverse dns lookup is a dns lookup that:
- query the PTR record with a reverse map name
- in order to get the DNS name (known also as the reverse DNS name)
- from a IP address
The inverse is called a forward dns lookup
This is not the physical hostname but the name known in the name service (DNS) The hostname has no relation to the ip.
Management
Get
You need to query the name service.
Nslookup
NSLOOKUP. Example from googlebot
nslookup 66.249.66.1
Name: crawl-66-249-66-1.googlebot.com
Address: 66.249.66.1
;; Truncated, retrying in TCP mode.
;; Got recursion not available from 10.255.255.254
x.x.x.x.in-addr.arpa name = xxx.xxx.tld.
x.x.x.x.in-addr.arpa name = xxx.xxx.tld.
where: x.x.x.x.in-addr.arpa is the reverse map name
Ping
Ping which will try to use WINS and DNS
ping -a 192.168.10.241
Pinging gerardnico01.gerardnico.local [192.168.10.241] with 32 bytes of d
ata:
Reply from 192.168.10.241: bytes=32 time<1ms TTL=64
Reply from 192.168.10.241: bytes=32 time<1ms TTL=64
Reply from 192.168.10.241: bytes=32 time<1ms TTL=64
Reply from 192.168.10.241: bytes=32 time<1ms TTL=64
Ping statistics for 192.168.10.241:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 0ms, Average = 0ms
host
host ip
dig
dig -x 104.19.167.23
Set
PTR record
A PTR record creates the reverse entry.