Re: Getting the FQDN using Net::Domain

[Anonymous Monk]

why the module behaves this way ?

Um, because that is why? I take the comment at its word :)

  # try looking in /etc/resolv.conf
  # putting this here and assuming that it is correct, eliminates
  # calls to gethostbyname, and therefore DNS lookups. This helps
  # those on dialup systems.

So if I see that correctly, relying on an entry in the "search" block is a bit risky, isn't it?

How exactly?

You can always use Sys::Hostname?

I see this caused problem for someone, Bug #73410 for libnet

[nickolsen]

Thanks for your reply and especially for mentioning the bug report.



How exactly?

As you can see in my example (and in the bugreport):
The "search" block contains only the local domain part by default, but it can be changed to whatever suits your needs. Therefor the module relies on information which might be right but don't have to be.

Sys::Hostname is not an option for me, as I need to know the FQDN and not only the host-part of the hostname. It calls "uname -n" [0], which does not have to know the domain-part.

Here's another example:

mobile:~# head -n2 /etc/resolv.conf
domain example.org
search intern.example.org example.org
mobile:~# python -c 'import socket; print socket.getfqdn();'
mobile.example.org
mobile:~# hostname -f
mobile.example.org
mobile:~# perl -e 'use Net::Domain qw/ hostfqdn /; print(hostfqdn . "\
+n");'
mobile.intern.example.org
mobile:~# perl -e 'use Sys::Hostname; print(hostname . "\n");'
mobile


Anyways, the bug report completely describes my issue, so maybe things will get fixed soon.

[0]: http://www.kernel.org/doc/man-pages/online/pages/man2/uname.2.html

[Anonymous Monk]

Anyways, the bug report completely describes my issue, so maybe things will get fixed soon.

Sure, if soon you mean 1 month to 3 or more years :)

Might get fixed quicker if you fork https://github.com/gbarr/perl-libnet