Hmm, they've always teached to me that . (dot) at the end of hostnames indicates the (hidden) Root domain:
blah.domain.com.[Root]
And my teachers always said that we don't need to write the final . because every domain belongs to the Root domain.
As for DNS servers for the Root domain, they are the reason for putting that "hint" files into our /var/named directory, "non"?
Regards,
Marlon Borba, CISSP
Abra�os,
Marlon Borba, CISSP.
"Por que 100? Bastaria
um se eu estivesse errado!"
--Albert Einstein, sobre o livro dos nazistas
"100 cientistas contra Einstein".
"Peter & Karin Dambier" <peter@peter-dambier.de> 05/19/05 9:00 AM >>>
[...]
Because programmes like
check_soa from the O'Reilly book "DNS and BIND" or
sendmail
believe it makes sense to force a dot at the end of
every name they look up.
There are nameservers in the root zone file that DNS will
not find. /etc/hosts is the only way to get them.
Dont forget to have both names with and without dot.
This thread needs to consider the layering of applications. E.g.,
Applications: Mail, Web, things using gethostbyname (host names, etc.)
Hmm, they've always teached to me that . (dot) at the end of hostnames
indicates the (hidden) Root domain:
blah.domain.com.[Root]
This much is true.
And my teachers always said that we don't need to write the final .
because every domain belongs to the Root domain.
This, not so much. Well, kinda.
Specifically, as I think was noted earlier on the thread in passing, as
well, that trailing dot is a hint *to your local name resolver* that
says "do not attempt to apply any locally defined DNS search path to
this name; look it up once, anchored to the DNS root[0], and if you get
an NXDOMAIN, believe it".
Semantically, that trailing dot, as it is presented to an application,
*is not part of the domain name*. It's ephemeral; only existing on the
machine where you type it in -- specifically, it does not get sent in
queries (SFIAK), even if you typed it in.
So, no, you *don't* need to write it, unless you as an application user
are trying specifically to pin the name on the root... but it's
invisible to the rest of the system, just as the names themselves are
invisible to the TCP stack once you've looked them up and opened a
stream.
Cheers,
-- jra