[clue-tech] BIND

[William]

Mike Staver wrote:

> As a quick follow up to this - I'm not thinking it has anything to do 
> with the version of bind I guess... I think it has to do with having a 
> name server listed as an NS record in the zone.  From what I'm 
> understanding, bind notifies those servers - not the ones listed in 
> the named.conf file (think allow-transfer ips), which are local IPs vs 
> the public IPs I have listed in the zone file.  Do any of you have to 
> deal with this, and if so, how do you get around it?
>
> Mike Staver wrote:
>
>> I am running the latest version of Bind that comes with CentOS 4.3, 
>> just installed today.  With older versions of Bind, I'm thinking back 
>> to RedHat 9 - when I'd update a serial number of a zone file, and 
>> restart named, it would broadcast out to the slaves and they would 
>> transfer over the latest zone file.  Now however, I update the zone 
>> file, restart bind, and the zones never transfer.  Is there some 
>> setting I'm missing so it doesn't just happen when the record expires?
>
My slave DNS providers are on other networks and I don't worry at all 
about pushing changes to them in real time.  As I learned it, TTL and 
expiry settings are what actually dictate when slaves update against the 
master.  When that update period lapses, the slaves query the master.  
If, and only if, the serial number differs, a zone transfer takes 
place.  Otherwise, the slaves maintain their local cache by updating 
only the expiry period, conserving bandwidth and processing cycles.  My 
logs seem to indicate this behavior.  I'll see no zone transfers for a 
while, until I make a zone update.  That night (several hours later), a 
zone transfer occurs.  My recommendation:  don't worry about it; this is 
normal.