some networking questions, I'm slightly confused

Gregory Nowak gnowak1 at uic.edu
Thu Dec 6 13:17:10 EST 2001 

Yes, sort of.
I'll have to talk to the guy running the service here when he gives me my second
connection, and see if I'll get another ip address or not, and if he knows if his router will support  bonding.
Greg


On Wed, Dec 05, 2001 at 10:00:36PM -0700, Darrell Shandrow wrote:
> Hi Greg,
> 
> Good deal; I'll be glad to do what I can to help, especially with a 
> specific implementation.  Did you get your answers regarding the two NICs 
> and the outside addressing?
> 
> Regards.
> 
> At 09:56 PM 12/5/2001 -0600, you wrote:
> >Thanks for the info even though I knew 99% of that.
> >I will be in touch if I need more help.
> >Again, thanks for a very good explanation (it's certainly better then I 
> >could've done (grin)).
> >Greg
> >
> >
> >On Wed, Dec 05, 2001 at 08:19:57PM -0700, Darrell Shandrow wrote:
> > > Hi Greg,
> > >
> > > I have stayed out of this until now because I haven't really had any time
> > > to respond properly.  My days are usually quite long lately.  Anyhow, I am
> > > a sys admin for a regional ISP; perhaps, I can help you.
> > >
> > > A domain is registered through a registrar like Network Solutions or
> > > register.com.  When the domain is registered, part of the required
> > > information includes the IP addresses for the primary and secondary name
> > > servers.  This information is then added to what are known as the root
> > > servers, which tell the entire world which primary and secondary name
> > > servers know how to answer lookup questions about your domain.  In other
> > > words, the root servers delegate authority to the specified primary and
> > > secondary name servers to answer questions concerning your domain
> > > name.  You could run one or both of these name servers yourself or have
> > > someone else do DNS.  It sounds like you are having someone else do 
> > primary
> > > and secondary DNS.  As I'm sure you already know, DNS is the domain name
> > > system, which points domain names to IP addresses, and which allows us to
> > > do neat things like browse to www.foxnews.com and send mail to
> > > nu7i at azboss.net instead of having to know all kinds of awful IP addresses
> > > just to perform the simplest of functions on the Internet.  So, DNS points
> > > a domain name to an IP address, but how does it work?  DNS information
> > > about a domain name is handled by name servers in the form of zone
> > > files.  Your domain exists as a zone file on the primary name server, and
> > > the secondary name server is usually set up as a slave to the primary.  In
> > > other words, the secondary name server gets its information (the zone 
> > file)
> > > from the primary name server and holds onto it, just in case the primary
> > > name server is unavailable for some reason.  The domain name system is
> > > really a very large, world wide distributed database.  A domain name
> > > contains various types of information which is managed in the form of
> > > various types of records.  The first type of record is SOA, which stands
> > > for start of authority.  This just specifies your primary and secondary
> > > name servers.  You see, if things were set up a certain way, your primary
> > > and secondary name servers could actually delegate authority for your
> > > domain to still other name servers, but this is not common
> > > practice.  Another important record type is the A record.  This is the
> > > address record, and your domain could have multiple A records, 
> > depending on
> > > how many subdomains you have set up.  For example my domain name servers
> > > have an A record for shandrow.com which points to 
> > 206.124.184.77.  There is
> > > also another A record for borg.shandrow.com, a subdomain, which also
> > > happens to point to the same IP address, though it could just as easily
> > > point to another IP address.  Another somewhat related record type is a
> > > CNAME, which stands for canonical name.  These records are used like
> > > aliases to point subdomains to other domains.  For example, I did use a
> > > CNAME record to point www.shandrow.com to shandrow.com, which means it 
> > also
> > > has the IP address 206.124.184.77.  Yet another important record type is
> > > the MX record.  MX stands for mail exchanger.  E-mail software uses these
> > > records when figuring out how to deliver e-mail on the Internet.  These
> > > records, numbered by priority, tell mail delivery software where mail
> > > should go when destined for a particular domain.  For example, my first MX
> > > record priority for shandrow.com (which is MX 10) points to
> > > borg.shandrow.com.  That is ultimately pointing to the Sendmail server
> > > which runs on the IP address 206.124.184.77.  But, again, this could have
> > > just as easily pointed to any Sendmail server which was configured to
> > > accept and deliver mail for the shandrow.com domain.  Additional MX 
> > records
> > > can be defined so that, if the server specified in the first priority MX
> > > record is unavailable for some reason, mail delivery software will try a
> > > second, third, fourth and so on server until it can deliver the mail.  I
> > > could, if configured properly, have a MX 20 pointing shandrow.com to yet
> > > another Sendmail server, which would be able to receive mail for
> > > shandrow.com in the absence of the primary mail server.
> > >
> > > Finally, there is reverse DNS.  This does the reverse of the domain name
> > > system; it translates IP addresses back to domain names.  You definitely
> > > want to have your DNS administrator set this up for your domain, because
> > > certain FTP sites, web sites and other types of services on the Internet
> > > use reverse DNS information for security purposes; they want to see that
> > > your forward DNS and reverse DNS point to the same place, or they may also
> > > want to verify that you have a domain which is or is not registered in a
> > > certain part of the world.  In my example, performing a nslookup on the IP
> > > address 206.124.184.77 will tell you that it reverses to 
> > borg.shandrow.com,
> > > which is a valid subdomain pointing to that same IP address.
> > >
> > > Anyhow, this will either help you or confuse you.  Please let me know if I
> > > can help you with specifics.
> > >
> > > Regards.
> > >
> > > At 06:38 PM 12/5/2001 -0600, you wrote:
> > > >Well, I'll actually be running a mail server for the building in which 
> > I live.
> > > >Instead of being regularly payed, my current connection will be free, and
> > > >I'll get a second free connection
> > > >They're running t1 over here through this HP networking gizmo that
> > > >plugs into the phone jack, and has an rj45 jack on it.
> > > >
> > > >
> > > >The reason I'm asking about the dns stuff is because
> > > >when I told the guy that I've looked at the mail admin docs, and am
> > > >seriously considering running the server,
> > > >his response to me was:
> > > >"so, I'll need to get you a domain with primary and secondary dns 
> > servers."
> > > >I said yes to this, but am carious about how his dns servers will know
> > > >where I exist
> > > >since he didn't ask for the name of my box.
> > > >I guess when he tells me he's got things set up,
> > > >my first question to him will be,
> > > >"what name do the dns servers know my machine by?"
> > > >
> > > >He's macroslop licensed, but not meaning to brag,
> > > >I get the impression that I may know more then he does without a license.
> > > >
> > > >In case some of you reading my post now are remembering a few of my other
> > > >posts, I decided
> > > >that getting my own domain name wasn't worth it.
> > > >He said that I could run a small web server here if I want. So, I don't
> > > >think he'd
> > > >have a problem with me running it as http://mybox.domain.
> > > >
> > > >This whole thing started when I got my service, and he came here to 
> > get it
> > > >all setup.
> > > >Not only was he impressed that I was the only one in the building so far
> > > >running anything other then windblows, but that it was Linux.
> > > >After my configuring tcp/ip both in windows and in Linux while he just
> > > >watched me do it and gave me my ip address and all the other stuff,
> > > >I asked if I would get a mail account.
> > > >He said no, because there is no body to run one yet.
> > > >Then he tentatively asked if I would be willing to perhaps do it, I said
> > > >I'd read the mailadmin docs and think about it,
> > > >and you know the rest.
> > > >
> > > >He's also looking to hire someone to run apachee.
> > > >But, I'm not touching that for now (grin).
> > > >Sorry for the long and personal post, but since Geoff asked,
> > > >I figured that some other people on this list may be wondering
> > > >why I'm asking theese questions, some of which may sound
> > > >dumb, but are for the most part so that I could make sure that what
> > > >I know is actually correct.
> > > >Greg
> > > >
> > > >
> > > >On Thu, Dec 06, 2001 at 09:29:48AM +1000, Geoff Shang wrote:
> > > > > On Tue, 4 Dec 2001, Gregory Nowak wrote:
> > > > >
> > > > > > 1. Say there is a primary and secondary dns servers on a domain
> > > > called mydomain.
> > > > > > Say also that there is a machine called mybox.
> > > > > > Also, I have ip addresses for primary and secondary dns servers on
> > > > mydomain.
> > > > > > Assumming all of the above, and assuming that I have permission to
> > > > officially be on mydomain which is a valid internet domain,
> > > > > > what do I do on mybox so that it would be resolvable
> > > > > > as mybox.mydomain on the net?
> > > > >
> > > > > Nothing.  It's the primary and secondary DNS servers that control 
> > how your
> > > > > host is resolved, not your box.  As long as mybox has the IP 
> > address that
> > > > > ns1.mydomain.com and ns2.mydomain.com think it has, you should be 
> > good to
> > > > > go.
> > > > >
> > > > > > 2. Say that I have to nics with 2 static ip address for the outside
> > > > world.
> > > > > > How do I set things up so that my box would use both
> > > > > > nics for outside access instead just either one nic or the other?
> > > > >
> > > > > As Chris said, what comes in where will depend on what address it 
> > is sent
> > > > > to.  What goes out where depends on a few things.  If you want to 
> > use one
> > > > > interface to access a particular host or network, you can set up a 
> > route
> > > > > accordingly.  If you want to access everything with both, you might 
> > be able
> > > > > to put 2 default routes (i've seen it done but don't know if it 
> > works and
> > > > > if it's supposed to work).  I saw you've been looking at bonding which
> > > > > might also work, but I don't know about it.
> > > > >
> > > > > Can I ask, why you have 2 NICs?  Is it just to get 2 addresses or 
> > are you
> > > > > connected to 2 networks?
> > > > >
> > > > > Geoff.
> > > > >
> > > > >
> > > > >
> > > > > _______________________________________________
> > > > > Speakup mailing list
> > > > > Speakup at braille.uwo.ca
> > > > > http://speech.braille.uwo.ca/mailman/listinfo/speakup
> > > >
> > > >_______________________________________________
> > > >Speakup mailing list
> > > >Speakup at braille.uwo.ca
> > > >http://speech.braille.uwo.ca/mailman/listinfo/speakup
> > >
> > >
> > > _______________________________________________
> > > Speakup mailing list
> > > Speakup at braille.uwo.ca
> > > http://speech.braille.uwo.ca/mailman/listinfo/speakup
> >
> >_______________________________________________
> >Speakup mailing list
> >Speakup at braille.uwo.ca
> >http://speech.braille.uwo.ca/mailman/listinfo/speakup
> 
> 
> _______________________________________________
> Speakup mailing list
> Speakup at braille.uwo.ca
> http://speech.braille.uwo.ca/mailman/listinfo/speakup

More information about the Speakup mailing list