notify delays using nsupdate

[Kevin Darcy]

Zain Al Abdeen wrote:

>Hi,
>
>I was testing notify on test boxes configured with just a couple of 
>zones. There is no load on either of the boxes acting as master and 
>slave servers respectively. Both server are running bind 8.4.1-REL.
>
>When a zone file is update manually on the master server and ndc reload 
><zone name> is issued, notify is send in almost 20secs and the slave 
>runs an AXFR almost immediately.
>
>When a zone is updated using nsupdate on the master server, notify is 
>issued in 2-10 mins and the slave runs an AXFR immediately. Whereas the 
>master server is responding immediately with the updated SOA after nsupdate.
>
>My questions are;
>Why there is delay in sending notify when using nsupdate ?
>Can the named be tuned to send notifies immediately after a successful 
>nsupdate ?
>What are implications for implementing nsupdate along with notify in an 
>environment where there are 25,000 plus zones and more than 5 slaves to 
>be notified ?
>Can using bind 9 or higher version of bind 8 improve the above mentioned 
>scenario ?
>
No, I'm not aware of any way to tune the outbound-NOTIFY-scheduling 
system. It's probably set quite conservatively because of all the sites 
out there being pounded by Win2K clients automatically registering 
themselves in DNS via Dynamic Update. If you have a dozens of slaves and 
multiple updates per second, you probably don't want to be sending 
NOTIFYs immediately as you get each update...

- Kevin