Reversed IP

I've been probing a network, just playing around with various commands to see what they'll do, what I can get them to do and that sort of thing. (Just a learning experience, I'm not trying to crack them.)

So I use the host command on them....and here's what comes up:

Quote:

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maccurdy@dburnet:~> host anl.gov
anl.gov has address 141.221.50.30
anl.gov has address 146.137.96.48
anl.gov has address 146.137.162.100
anl.gov has address 146.139.250.20
maccurdy@dburnet:~> host -l 146.137.96.48
48.96.137.146.in-addr.arpa domain name pointer rhino221.anl.gov.
maccurdy@dburnet:~> host -l 146.137.162.100
100.162.137.146.in-addr.arpa domain name pointer tiger201.anl.gov.
maccurdy@dburnet:~> host -l 146.137.250.20
Host 20.250.137.146.in-addr.arpa not found: 3(NXDOMAIN)

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Notice that when it returns the lines, it reverses the IP addresses...

Quote:

---

maccurdy@dburnet:~> host -l 146.137.96.48
48.96.137.146.in-addr.arpa domain name pointer rhino221.anl.gov.

---

Does anyone know why its doing this? Is it just returning a weird echo?

Your problem is a typo:

The ip is 146.139.250.20

you typed

host -l 146.137.250.20

That one instance does seem to be a typo. But the same thing happens when I do it for other IPs. In any case...I don't see how messing up the IP like that could account for what's going on.

I get the same thing.

[root@tuxbox root]# host anl.gov
anl.gov has address 146.137.96.48
anl.gov has address 146.137.162.100
anl.gov has address 146.139.250.20
anl.gov has address 141.221.50.30

[root@tuxbox root]# host -l 146.137.96.48
48.96.137.146.in-addr.arpa domain name pointer rhino221.anl.gov.

[root@tuxbox root]# host -l 146.137.162.100
100.162.137.146.in-addr.arpa domain name pointer tiger201.anl.gov.

[root@tuxbox root]# host -l 146.137.250.20
Host 20.250.137.146.in-addr.arpa not found: 3(NXDOMAIN)

[root@tuxbox root]# host -l 146.139.250.20
20.250.139.146.in-addr.arpa domain name pointer hippo308.anl.gov.

[root@tuxbox root]# host -l 141.221.50.30
30.50.221.141.in-addr.arpa domain name pointer bison752.anl.gov.

[root@tuxbox root]# host -l 141.220.50.30
Host 30.50.220.141.in-addr.arpa not found: 3(NXDOMAIN)

One of us is completely mis-understanding the other...and it may well be me.

Why is it outputting the IP address in reverse? It doesn't seem to make sense to me. Is it just how it is returning the data? An echo function? What?

Nothing in man host was able to shed any light, it just gave me some more information on the modifiers. ::Toying with -la right now::

Ok, look at

http://www.jhsoft.com/help/df_reverse.htm

[spill@h3r3tic3 spill]$ host 100.162.137.146.in-addr.arpa
[spill@h3r3tic3 spill]$ host -l 100.162.137.146.in-addr.arpa
;; Connection to 192.168.0.1#53(192.168.0.1) for 100.162.137.146.in-addr.arpa failed: connection refused.
[spill@h3r3tic3 spill]$ host 100.162.137.146.in-addr.arpa > host.txt
[spill@h3r3tic3 spill]$

I was just messing around trying that and I don't know what it did for the first and last command above. It would just go to the next line when I hit enter. When I sent the output to the text file there was nothing in it(which isn't surprising because there wasn't any output). So how come I didn't get any errors if this command doesn't do anything?

edit
here is some more to clarify. I was just wondering why I got no error.

[spill@h3r3tic3 spill]$ host 1.0.168.192.in-addr.arpa
Host 1.0.168.192.in-addr.arpa not found: 3(NXDOMAIN)
[spill@h3r3tic3 spill]$ host 100.162.137.146.in-addr.arpa
[spill@h3r3tic3 spill]$ host 146.137.162.100.in-addr.arpa
Host 146.137.162.100.in-addr.arpa not found: 3(NXDOMAIN)
[spill@h3r3tic3 spill]$

Thanks! THAT was helpful. I appreciate it.