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For example I do in Linux using host command:

host yy.yyy.yy.y


Host not found: 3(NXDOMAIN)

Then I repeat host command in a reverse with z.zzz.zz.z than I got a result of pastyy.yyy.yy.y:

Host z.zzz.zz.z


Host not found: 3(NXDOMAIN)

What is occured and why is that result?

When I try got a WHOIS address of z.zzz.zz.z and yy.yyy.yy.y I got for example:

  yy.yyy.yy.y --> KOREA NIC
  z.zzz.zz.z --> JAPAN NIC

A result via WHOIS is on properly address, but when I use host command it result same.

For others who not understand my question look at this:

xx@yy:$ host
Host not found: 3(NXDOMAIN)
xx@yy:$ host
Host not found: 3(NXDOMAIN)  <--- Why ? WHOIS don't respond this IP
share|improve this question

closed as unclear what you're asking by Iain, Ward, Tom O'Connor Aug 11 '13 at 19:38

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question.If this question can be reworded to fit the rules in the help center, please edit the question.

Your question is utterly unclear. Use the real IP addresses in your question. – Dennis Kaarsemaker Aug 11 '13 at 17:18
Are you on IP a.b.c.d and are you trying (Note the reversed sequence in abcd and dcba) – Hennes Aug 11 '13 at 18:01
I believe the OP has no idea at all what he/she's doing. – Marki Aug 11 '13 at 21:40
up vote 0 down vote accepted

I also don't understand your question fully, but:

If you want to perform a reverse lookup e.g. of using the host command you simply type


That's it. You don't need to use anything or invert the bytes when using the host command in order to perform a reverse lookup.

share|improve this answer
Look at question. I've edited. – Marin Sagovac Aug 11 '13 at 20:24
Read my answer again. I believe it perfectly explains what you want to know. Maybe you should also read some docs:… – Marki Aug 11 '13 at 21:00
Sorry, it's reversed. I have bad day sorry! I know know. Solved. – Marin Sagovac Aug 11 '13 at 22:56

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