get networking info

dancko · 11-17-2020, 05:55 AM

Hi to all,

I would need to know some network information and I don't know how to do it.
Please, can anyone help me?
In particular, Is there a way to know if two different host name refer to same physical machine?
Example, host A and host B refer to same machine M.
Or, Is there a way to know if two different host name refer to two different virtual machine installed on the same physical machine?
Example, host A and host B refer respectively to virtual machine A and virtual machine B installed on the same physical machine M.

thanks in advance.

berndbausch · 11-17-2020, 06:45 AM

Quote:

Originally Posted by dancko

In particular, Is there a way to know if two different host name refer to same physical machine?

If you mean domain name, you can perform a reverse DNS lookup to get all names. Example: In my home network, the same machine is named odroid and homeserver.

Code:

$ dig -x 192.168.1.16

; <<>> DiG 9.10.3-P4-Ubuntu <<>> -x 
...
;; QUESTION SECTION:
;16.1.168.192.in-addr.arpa.     IN      PTR

;; ANSWER SECTION:
16.1.168.192.IN-ADDR.ARPA. 86400 IN     PTR     odroid.home.
16.1.168.192.IN-ADDR.ARPA. 86400 IN     PTR     homeserver.home.
...

Quote:

host A and host B refer respectively to virtual machine A and virtual machine B installed on the same physical machine M.

I suppose that depends on the hypervisor. For KVM, I think VM names are unique.

This is a strange question. If you have a problem, state the problem. Is anything not working as expected?

dancko · 11-17-2020, 09:41 AM

First at all thanks for the response.

Quote:

Originally Posted by berndbausch

This is a strange question. If you have a problem, state the problem. Is anything not working as expected?

Effectively, if two host name refers to two different machine, know also if that two machine are virtual machine it makes no sense.

Anyway, my question was only for curiosity. I have no problem.

thanks.

dugan · 11-22-2020, 06:23 PM

Just resolve the domain name and see if they resolve to the same IP, no?

I mean, just "ping -c1" should do it in most cases.