please clarify "virtual hosting"

Tue, 26 Dec 2000 23:07:21 -0700 (MST)

It all depends on how the DNS server the domain from NSI is pointed.
You can configure the DNS server to point to many different IP addresses 
depending on the subdomain or record type.  MX records direct
mailing an IP address; you can also specify extra addresses in case
the main one is down.  My guess is that DNS is currently pointed
to an invalid IP address, but mail is being routed by backup servers
through the MX records that have been setup.  To view this fire up
`nslookup` and type the following commands

> set type=mx
> {enter domain name}

Example:
> set type=mx
> slashdot.org
Server:  dns1.adv-computer.com
Address:  64.36.30.35

Non-authoritative answer:
slashdot.org    MX preference = 10, mail exchanger = mail.upn.net
slashdot.org    MX preference = 20, mail exchanger = mail2.upn.net

slashdot.org    nameserver = ns1.andover.net
slashdot.org    nameserver = ns2.andover.net
slashdot.org    nameserver = ns3.andover.net
ns1.andover.net internet address = 209.207.224.196
ns2.andover.net internet address = 209.207.224.197
ns3.andover.net internet address = 209.192.217.104
>

HTH,
Eden

Quoting "David P. Schwartz" <davids@desertigloo.com>:
> Thanks, George.  However, I'm still wondering what the differences are
> between the web virtual hosting and the email routing.  It would
> appear that two different mechanisms are being used for domain name
> recognition.  I recently discovered that a domain name I had hosted as
> a virtual domain alias got "disconnected", in that if you tried to reach
> it through a web browser, it was gone.  But, email addressed to
> that domain got right through.  So I'm puzzled -- what's handling the
> domain name recognition for emails?
> 
> -David
> 
> George Toft wrote:
> 
> > Not much, really, IF you use the right software.
> >
> > IMHO, what you are asking is outside of their cookie-cutter
> mentality.
> > Yes, it is easy, but will they do it?  We did this all the time at my
> > last job (a web hosting company).  IF they are set up to do it, all
> > they have to do is run a script (less than one minute including
> login,
> > and that's for a slow typist).
> >
> > It all comes down to money and stats.  What you are asking is outside
> > of the 95% of requests that they are set up to handle.  It is easier
> > to say no than to spend a couple hours setting it up.  If they pay
> > their SysAdmin $50/hr (salary + benefits) and it takes him/her two
> > hours, they are out $100.  How long will it take them to recover $100
> > from your account?  Ten months?  It's not worth it to them because
> > that's how long it will take them to recover their investment,
> > meanwhile, they've lost out on the revenue they would have collected.
> > They would rather say no, or even let you go than to embark on a
> > venture that sets them back ten months in revenue.
> >
> > If enough people ask for it, which puts the request into the 95%
> > category, they'll set it up, or lose business to those who will set
> > it up.
> >
> > At my last job, that one minute (one time) script brought in
> $10/month.
> > I had the account set up script automated, and that brought in
> anywhere
> > from $50-$300, depending on the account.  One minute of my time made
> > the company $50-300.  Pretty cool.
> >
> > George
> >
> > "David P. Schwartz" wrote:
> > >
> > > I'm wondering what is the relationship between virtual hosting of a
> web site domain vs. a
> > > mailbox domain
> > >
> > > I have had an account on impulsedata.com, which is an ISP in town
> here.  They host a few
> > > domains of mine, all of which are mapped to the same place (one web
> site, lots of
> > > aliases).  All of the email gets mapped to my main userid at
> impulsedata.com.
> > >
> > > I've played a bit with a non-dedicated system hosted on a Cobalt
> RaQ3 and RaQ4.  I can
> > > route a domain by changing the DNS entries at DirectNIC or InterNIC,
> and the host needs to
> > > know what the domain name is so they can set things up there.  This
> works for single
> > > domains.  Neither host would support aliases of either web or email
> domains.
> > >
> > > Some hosts advertise that they'll allow virtual hosting of multiple
> domains on one site
> > > (like what I'm doing at ImpulseData.com right now), but they they
> say they won't allow
> > > multiple email domains.  IOW, I can set up a main virtual host as
> abc.com, then aliases of
> > > abc.net, def.com, and def.net, but they won't allow email to the
> latter three to be
> > > delivered.
> > >
> > > I know that you can flip things around from Apache's conf's, like
> fred.abc.com vs.
> > > www.abc.com/~fred.  But how are these kinds of things handled for
> email?  I get the
> > > impression email routing is handled differently, although the domain
> naming seems like it
> > > ought to be subordinate to the web routing.
> > >
> > > Thanks
> > > -David
> > >
> > > ________________________________________________
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> 
> 
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