Re: [cobalt-users] Primary, secondary, auto-update, still confused

[flash22@xxxxxxx]

On Thu, 14 Feb 2002, Patrick wrote:

> services resolving to my ISP. This seems correct (though the primary
> upstream PTR record was not resolving to my hostname... it now is...) 

Try to keep the domain names seperate from the PTR stuff, they are in fact
totally different things, tho from your point of view you see them in the
same place, from outside your machine they are totally unrelated 

> The issue is - if I add a sub-domain, i.e., another virtual site (with it's
> own domain name) under the same IP - do I need to inform my ISP of the

Don't confuse 'zone' with 'domain name' , When a primary gives info to a
secondary it's giving it a zone. the zone includes the domain name the
zone is named for, and all sub-domains in it, so no, you don't need to
tell them anything as long as you are adding a name that has the same
'ending' as your zone

eg:    foo.com is a zone, it's also a domain name
   www.foo.com is a domain name in the zone 'foo.com'
   www.bar.com is a domain name, but it's NOT in zone foo, it's in zone
               bar.com

When you say 'sub-domain', i assume you mean the second one of those, but
you might not, and i might not, the term is slightly vague, you might mean
www.blarg.foo.com , which is also a domain name...Some folks ignore the
'www' when they say 'subdomain' ...

The zone will send everything in the specified zone to the slave...
so if the slave handles the zone 'foo.com' , and you have in your
master/primary foo.com,www.foo.com,www.blarg.foo.com, they all go 

[I'm simplifiing a bit, but for what you are doing it should be about
right]


> This from Jeff:
> >Find out from whoever gives you your connectivity whether or not
> >they've delegated "reverse" DNS to you; if they have, set up ONE reverse

Jeff is referring to your PTR records, as i said above, that is a totally
different issue....

When you registered a domain name , you granted your self the authority to
answer for it via your nameservers, you don't , and in fact, can't do that
for PTR / in-addr names, they are related to who owns the IP addresses,
which is your ISP, that's why you have to find out what they are doing ..

Assuming they allow you to set names for IP addresses with PTR records,
they have either pointed their nameserver at you, in which case you look
like a primary for answering PTR queries, or they are leaving their
nameserver as master, but letting it update from your nameserver , either
way your server has to be a master for the information in the PTR record
because it knows the answer to the queries, the only difference is from
your ISP's point of view, and the possible need for a stray NS record
...if you have one PTR record working, you probaby got that part right...

> Surely my ISP's secondary is part of this upstream process - If I am not
> running (a) PTR record then surely no names will resolve for a requested IP

Not true, the presence or absence of PTR records has nothing whatsoever to
do with your ability to resolve forward domain names, MX's etc

Don't confuse them, they are seperate

'A' - convert name into IP address
PTR - convert IP address into name

You can do either without necessarily being able to do the other

> Perhaps all of the above has nothing to do with whether the secondary
> updates or not?

Correct, the ability to update zones from your master to their secondary
only requires that you grant access, and they allow accesss, and they have
a list of zones that are being handled

> >Do NOT set up "secondary" records.  You only need them if your doing
> >secondary DNS for others, where the primary is hosted elsewhere.

Read what Jeff said there, it's important :)

> 
> I don't have an A record for my ISP's secondary - should I? (though I do
> have the secondary reflected in the SOA records)?

No, you can't anyhow, it's *their* domain name, you can't give out records
for it, you do however need to resolve *your* name for their server ,
which is presumabily the 'secondary' nameserver in your whois record, with
an ip address of their server. Only if you named it yourself, if you
registered it to *their* name, you don't want an A record for it, it's not
your name in that case.

> Okay - so I am confused - if I change primary zone files (i.e., add a
> sub-domain?) - the secondary zone files will update? An added twist to all

Yup, unless below is true

> this is that the new sub-domain I am trying to create presently resides
> elsewhere (though it doesn't resolve.) - so I am wary of submitting the

If it's in whois, it's not a subdomain, it's a top level domain, therefore
it needs a zone...and you have to tell your isp ;P

> domain change to the nameserver authorities without seeing the secondary
> update... and it still reflects the legacy dns... so will give an error...

If it doesn't resolve, it's broken anyway, does it matter?

gsh

ps: You really ought to get a copy of the bind book , this stuff is more
confusing than it looks sometimes :)