Address Sorting NOT in V8

[Kevin Darcy]

craigjca at my-deja.com wrote:

> No, sortlists are not what I really want.

Are you sure? See below.

> What I really want is the
> feature the developers of BIND 8 conveniently left out (see paragraph 3
> on page 240 of the 3rd edition O'Reilly book).

Yes, they took out address sorting altogether for a while in BIND 8. But
they added sortlist and rrset-order back in as of 8.2, which is subsequent
to the 3rd Edition of the O'Reilly book. So, reading the book may leave you
with the impression that address sorting is impossible with BIND 8. But
it's not.

> This was such an elegant
> load balancing solution for a mid-sized site.  I have four 1024 node
> "subnets", and I'd connect my servers to each of them, call them all the
> same thing (along with an alias, for good measure), and with DNS 4.94,all
> the clients on netA got serverA, clients on netB got serverB, etc.

acl netA { 192.168.0/22; };
acl netB { 192.168.4/22; };
acl netC { 192.168.8/22; };
acl netD { 192.168.12/22; };

options {
    sortlist { { netA; }; { netB; }; { netC; }; { netD; }; };

...




- Kevin


> Why, oh why, did they take this out?  Now there's no guarantee what
> address you're going to get, and I don't believe sortlists can replace
> the lost functionality.  Any help is appreciated.
>
> Craig
>
> In article <38E15508.986A8B62 at daimlerchrysler.com>,
> Kevin Darcy <kcd at daimlerchrysler.com> wrote:
> > craigjca at my-deja.com wrote:
> >
> > > I found rrset-order in the source for named, but it isn't discussed
> in
> > > O'Reilly from what I can tell. What is the best place to find
> details
> > > on this topic?
> >
> > Um, did you try the documentation in the BIND distribution? "The
> > book" only covers through BIND 8.1.2 and the address-sorting features
> were
> > added in BIND 8.2, so you'll have to make do with ISC's docs for now.
> >
> > > Again, what I need. If I'm on network A, and the server I am trying
> to
> > > connect to is on A, B, and C (by the same name), when I do an
> "nslookup
> > > server" I should always get back the servers A address first.
> >
> > Sounds like "sortlist" is what you want. But you have to configure
> each
> > network in the named.conf file. If I recall correctly, BIND 4 just
> > *assumed* a network size based on how your local interfaces were
> > configured. Since that's not always a good assumption, and because
> > sometimes you may wish to selectively override the behavior, BIND 8
> has
> > you specify all of the networks explicitly.
> >
> > - Kevin
> >
> > > In article <OFaE4.45$5p5.1536 at burlma1-snr2>,
> > > Barry Margolin <barmar at bbnplanet.com> wrote:
> > > > In article <8br6fo$qbu$1 at nnrp1.deja.com>, <craigjca at my-deja.com>
> > > wrote:
> > > > >Version 4 of BIND contained a very useful tool
> > > > >called address sorting. This was great for
> > > > >multihomed hosts - you look up a name, and you'd
> > > > >get back the network address of the network you
> > > > >were on. If you weren't on any of networks the
> > > > >multihomed host was, then BIND roundrobined.
> > > > >
> > > > >For some reason, they have apparently left this
> > > > >feature out of V8. Does anyone know why? Is
> > > > >there a way to turn it back on?
> > > >
> > > > Is "rrset-order" what you want?
> > > >
> > > > --
> > > > Barry Margolin, barmar at bbnplanet.com
> > > > GTE Internetworking, Powered by BBN, Burlington, MA
> > > > *** DON'T SEND TECHNICAL QUESTIONS DIRECTLY TO ME, post them to
> > > newsgroups.
> > > > Please DON'T copy followups to me -- I'll assume it wasn't posted
> to
> > > the group.
> > > >
> > > >
> > >
> > > Sent via Deja.com http://www.deja.com/
> > > Before you buy.
> >
> >
>
> Sent via Deja.com http://www.deja.com/
> Before you buy.