single class B zone vs multiple class C zone

Sat May 26 00:59:33 UTC 2001

Yes, if all RR in the zones are dynamic, I wouldn't care....but all the
zones contain some static records.  My static name server is authoritative
for the entire class B zone.  My dynamic domain is a subdomain.  Since we
do everything on the class C subnet basis, there are both static and
dynamic ip address assignment for each subnet.  I had to delegate the
entire class C to the dynamic server, even though the static records are
actually in the static class B zone.  Actually the static records have to
be placed in both the dynamic server and the static server...It's quite a
mass...I know-)...

I'm trying to merge the dynamic and static into one dynamic environment.  I
will still have large number of static records since all critical servers
and printers will stay static.  My design right now is to have one master
server which accepts dhcp updates, and two slaves (these two slaves are
responsible for answering queries.  The master ddns server will be pretty
much invisible to the users).  I also have a database that maintains all
the static records and generates a forward and reverse zone each night.
Now where would be a better place to place the static records?  If on the
master ddns server,  each night when the static records get updated, I'll
have to pick out the dynamic records and may have to stop the named daemon
to do so.  This certainly will affect end users.  If place on the two
slaves, all I need to do is to make sure the zone transfer isn't happening
at the time I need to update the static records.  I can pick out either the
static records or the dynamic records and keep the same serial.  That way
after the zone has changed, the transfer should happen as usual.  Is this
correct?  Am I missing anything?

Thank you in advance!

Hannah Day

                    Kevin Darcy                                                                                   
                    <kcd at daimlerchr       To:     bind-users at isc.org                                              
                    ysler.com>            cc:                                                                     
                    Sent by:              Subject:     Re: single class B zone vs multiple class C zone           
                    bind-users-boun                                                                               
                    ce at isc.org                                                                                    

                    05/25/01 05:18                                                                                
                    PM                                                                                            

Yes, you may run into performance issues, since the zone will be larger and
probably change more frequently. This will greatly increase your
zone-transfer
overhead. On the other hand, it may reduce your serial-number-query
overhead,
since there are now less zones for the slave to check. But the
serial-number-query overhead is usually a small fraction of the
zone-transfer
overhead, so you'll probably lose more than you'll gain here,
performance-wise.

Why do you care to consolidate all of those reverse zones? If you're
maintaining the data in those zones automatically via Dynamic Update from
your
DHCP server, then it shouldn't really matter whether they are separate
zones
or all one zone.

- Kevin

Hannah O Day wrote:

> I have both dhcp and ddns servers (BIND4.93) that run on Aix boxes.  I
have
> been config all reverse zones on the per class C subnet basis.  I'm now
> upgrade the server to BIND8.2.3.  I want to config the reverse with only
> one class B instead of many class Cs.  Could anyone tell me if this will
> cause any performance issues since the updates will now happen to the
> entire class B instead of class c?