probably simple question

[Kevin Darcy]

This is an *incredibly* Frequently-Asked Question...

Go back to basics: what is the simplest way to get a name to resolve to
an IP address? An A record. That works just fine in this context. The
problem is, once people learn how to do CNAMEs, they often go CNAME-crazy
and forget the fine print with respect to CNAMEs, i.e. the "CNAME and
other data" rule. CNAMEs can't co-exist with other record types, so, by
inference, you can't have a CNAME be the same as a zone name, since a
zone has at least an SOA record (and, arguably, at least one NS record as
well), and the CNAME can't co-exist with it. Just use an A record and be
happy.

By the way, you made an assumption that "there must be some aliasing
going on". But there's no need to guess here: if you use a real
DNS troubleshooting utility like "dig", you can see whether a name is
aliased or not just by looking at the output. (It's possible within
"nslookup" also, but you have to turn on debug mode for this). You'll
find that the zone names out there which also resolve directly to
IP addresses are all A records. (Or perhaps I shouldn't say "all" --
I guess it's conceivable that some broken DNS implementation might break
the "CNAME and other data" rule).


- Kevin

Jason Timmons wrote:

> Here's my situation.  I imagine this is dealt with every day, there
> must be something I am missing about the whole DNS deal.
>
> Let's say I own whatever.com.  I run the primary DNS server for
> whatever.com.  I can add a records all day long for this.whatever.com
> or that.whatever.com, and they resolve, and their hosts can be pinged
> and telnetted to, etc.  What if I just want to be able to
> ping/telnet/etc.  whatever.com.  I want anyone on the net to be able
> to type
>
> telnet whatever.com
>
> and reach a host.  Now, per my understanding of DNS and delegation,
> etc., the authority that holds the record for .com should have an a
> record somewhere with an IP for the host 'whatever' in the zone .com.
> This authority in my case would be NSI.  Now, I've never heard of
> anyone doing that, but I know very well that there are many hosts with
> only one name left of the .com (or .org, etc) that can be reached this
> way.  Any ISP, for example.  So, there must be some aliasing going on.
> You can't just make an a record with a blank hostname, and no dots are
> allowed in the a record either.  Does it have something to do with
> CNAME?
>
> I've read the whole O'Reilly DNS book, but have not found this answer.
> I am assuming its right there in front of me, and I've just missed it.
>
> TIA
>
> -jason timmons