Quoting Christopher Tolley ([EMAIL PROTECTED]):
> Damn...Since I messed that up completely, here is another try:
OK. Well I know you're trying to help the guy with his DNS issues, but
I'm afraid I read your mail and decided I had to comment.
> Your IP reverses back to this:
>
> 42.147.30.206.in-addr.arpa. 1D IN PTR server.lsbsolutions.com.
>
> Same potential problem. The PTR should point to lsbsolutions.com,
> not server.lsbsolutions.com
How is that? There is an A record for server.lsbsolutions.com in the
DNS.
> Also, you should be using CNAMEs instead of multiple A records. The
> only time you need more than one A record in a zone is when it's
> different.
I don't think your advice is going to solve his problem, nor do I
quite understand your reasoning. Granted that using CNAMEs can be
convenient when services are moved, but there is absolutely no harm in
not using CNAMEs at all. CNAME lookups take longer, even.
For spam-checking, the remote host will do a lookup on the A and MX
record for your domain name. If it gets neither, but there are NS
records for the domain, the message is deferred. If no NS records,
it's not in the root servers, it gets rejected.
I don't see how messing around with all of his records is going to
change the result. In my mind, what is likely happening is that the
lookups are merely timing out, so the message is deferred. I noted a
peculiar delay when querying those name servers. When the records are
expired from the cache on the name server those machines are using, it
could be they aren't getting any answer from teoi.net in a timely
manner, so the mail is deferred.
It could also be true that the name servers those mail servers are
using just plain suck or the mail servers themselves need to be
reconfigured (perhaps they are using name servers in a seperate
collision domain and the link in between is congested, hell I dunno).
Forward and reverse lookups match just fine. I don't see a thing wrong
with that zone, really.
> smtp 1D IN CNAME server <--------you are doing nested
>lookups here
That CNAME points to a valid A record, so do the others. How does
that create a "nested lookup?"
> localhost 1D IN A 127.0.0.1 <-------localhost.lsbsolutions.com? ppl
> can't get to it, so why in DNS?
Hmm, why indeed? Well, how about for software that doesn't use
/etc/hosts, like qmail? If it weren't in the DNS, they would not even
know what the IP address for "localhost" is! That's but one argument
in favor of a "localhost" A record.
I think geographical and network-diverse name servers are what he
needs. If you note, they are both within the same network, which we
know can lead to DNS outage. :)
Aaron
