At 02:23 PM 1/6/02 -0500, you wrote: > > From: Julian Opificius <[EMAIL PROTECTED]> > ><snip> > > > Now, if you put a forwarder statement in your zone file, then your DNS > > server will go to your ISP's DNS server(s) before trying to resolve an > > address itself. Your ISP's DNS server has to do all the work. That's fine: > > this will reduce the load on your machine's DNS server. Your DNS sever > will > > still cache the results, however. The forwarding statement only changes > HOW > > it goes about getting names resolved, it doesn't stop it from caching the > > results. > > > > Now, on to forwarding. > > Given the setup I was talking about in the first place was four > machines on > > a LAN, one of which was a Linbox running bind, there's no point in running > > a DNS server in the first place if all I'm going to do is concentrate all > > DNS request to the Linbox then pass them up to my ISP's DNS server, is > > there? I might as well point each of my LAN workstations at my ISP's DNS > > server and be done with it. They'd all go my ISP's server individually for > > their answers. > > > > You see, in one of the references Dave made yesterday, it was claimed that > > setting up a forwarding server reduces local network load. I assure you > DNS > > requests don't amount to a hill of beans on even a modest LAN, compared to > > the actual data that is transferred once the address is resolved. Look at > > the size of even a modest web page these days. > ><snip> > >I certainly agree that DNS traffic is minimal. I was interested in >doing this as a learning experience not because I thought it was going >to make any difference in the performance of my small LAN.
Oh me too. I don't need a DNS server for 4 machines! It's for the purpose of learning. >I'm still not convinced that using the forwarders isn't the >best/correct solution. For you or me it certainly may be the _best_ solution - because it reduces the work done by our local DNS server :-) Correct vs incorrect is not a useful assessment in my eyes, as it would certainly work. > >From man named.conf (BTW, does anybody else on a RedHat 7.2 system get >strange lines when typing "man named.conf" - it outputs a bunch of >lines like "mdoc warning: Empty input line #2064" before getting to >the man page). I'd worry about that if I were you ;-) >----------------------------------------------------------------- > > Forwarding > >The forwarding facility can be used to create a large site-wide cache >on a few servers, reducing traffic over links to external nameservers. >It can also be used to allow queries by servers that do not have >direct access to the Internet, but wish to look up exterior names >anyway. Forwarding occurs only on those queries for which the server >is not authoritative and does not have the answer in its cache. > >----------------------------------------------------------------- > >Again this (specifically the last line) seems to indicate this is what >to do. If the answer can be found in my machine's DNS cache, it is >used, otherwise it uses my ISPs nameservers to do all the work (and >then presumably caches the result). Any DNS server does that. That's what DNS serving is :-) Even a DNS server that talks to a forwarder does caching. The only difference is that if (and only if, by the way, unless you have the entry "forward only") the local DNS server is successful in getting an IP resolved by the upstream (forwarding) DNS server, then it doesn't have to do the Sherlock Holmes work itself. Which is to say that if the upstream server doesn't get the job done "in time", then the local DNS server will go out and do the work itself, forwarding statement or no. It's perfectly OK to use your ISP's server as a forwarding server, I'm not saying it's not. If you have a busy or a slow machine it's not a bad idea. All I am saying is that doing so in a single-DNS server network is not what the forwarding feature was intended for. That is no reason not to use it though ! Julian. =============== >Dave > > > >_______________________________________________ >Redhat-list mailing list >[EMAIL PROTECTED] >https://listman.redhat.com/mailman/listinfo/redhat-list ---------------------------------------------------------------- Just because I'm paranoid doesn't mean they aren't after me ... Julian Opificius. ICQ 3268206. ---------------------------------------------------------------- _______________________________________________ Redhat-list mailing list [EMAIL PROTECTED] https://listman.redhat.com/mailman/listinfo/redhat-list
