Can "host" perform reverse DNS'ing?

ganninu · 11-09-2003, 06:28 AM

I'm exploring some Linux networking tools, and came across "host". I've used it to resolve IP addresses (forward DNSing).Can I use it to perform reverse DNSing? (I have no dns servers at home - I just want to use "host" as a tool to DNS lookup IP addresses). This is what i get:

root@tiger:~$ host <some ip address>
<some ip address> does not exist, try again

hw-tph · 11-09-2003, 06:41 AM

I have also noticed that host doesn't always work for reverse lookups. Like this one:

Code:

hw@baron:~$ host www.google.com
www.google.com is an alias for www.google.akadns.net.
www.google.akadns.net has address 216.239.59.99
hw@baron:~$ host 216.239.59.99
Host 99.59.239.216.in-addr.arpa not found: 3(NXDOMAIN)

...but it works flawlessy for others. Feed www.yahoo.com to it and it will return a set of hosts, pick one of those hosts and it will resolve to the real name:

Code:

hw@baron:~$ host www.yahoo.com
www.yahoo.com is an alias for www.yahoo.akadns.net.
www.yahoo.akadns.net has address 216.109.118.78
www.yahoo.akadns.net has address 216.109.118.65
www.yahoo.akadns.net has address 216.109.118.67
www.yahoo.akadns.net has address 216.109.118.68
www.yahoo.akadns.net has address 216.109.118.69
www.yahoo.akadns.net has address 216.109.118.70
www.yahoo.akadns.net has address 216.109.118.73
www.yahoo.akadns.net has address 216.109.118.76
hw@baron:~$ host  216.109.118.70
70.118.109.216.in-addr.arpa domain name pointer p7.www.dcn.yahoo.com.

Very weird. I would also like some info on what's really going on.

Håkan