rdns
Quickly look up reverse DNS names. One of them or lots of them.
Look them up by IPv4 address:
$ rdns 192.0.43.7
# 192.0.43.7
192.0.43.7 icann.org.
Look them up by IPv6 address:
$ rdns 2001:500:88:200::8
# 2001:500:88:200::8
2001:500:88:200::8 iana.org.
Look up ranges of them:
$ rdns 192.0.43.7/29
# 192.0.43.7/29
192.0.43.1 43-1.any.icann.org.
192.0.43.2 43-2.any.icann.org.
192.0.43.3 43-3.any.icann.org.
192.0.43.4 43-4.any.icann.org.
192.0.43.5 43-5.any.icann.org.
192.0.43.6 43-6.any.icann.org.
192.0.43.7 icann.org.
Look them up by forward name:
$ rdns arin.net
# arin.net
2001:500:4:c000::43 www.arin.net.
2001:500:4:c000::44 www.arin.net.
199.43.0.43 www.arin.net.
199.43.0.44 www.arin.net.
Look them up by all of the above at once:
$ rdns 192.0.43.7 2001:500:88:200::8 192.0.43.7/29 arin.net
# 192.0.43.7
192.0.43.7 icann.org.
# 2001:500:88:200::8
2001:500:88:200::8 iana.org.
# 192.0.43.7/29
192.0.43.1 43-1.any.icann.org.
192.0.43.2 43-2.any.icann.org.
192.0.43.3 43-3.any.icann.org.
192.0.43.4 43-4.any.icann.org.
192.0.43.5 43-5.any.icann.org.
192.0.43.6 43-6.any.icann.org.
192.0.43.7 icann.org.
# arin.net
2001:500:4:c000::43 www.arin.net.
2001:500:4:c000::44 www.arin.net.
199.43.0.43 www.arin.net.
199.43.0.44 www.arin.net.
Installation
$ go get -u doof.net/cmd/rdns
Happy resolving.