[Pdns-users] Slave AXFR not working 100% at high rates

[Tom van Leeuwen]

Hi list,

Probably same issues as in this very old post, never answered though: 
http://mailman.powerdns.com/pipermail/pdns-users/2006-July/003655.html
I'm also taking the same subject.

I've been running pdns in my company for a few years now and have been a 
happy user.
We have 1 pdns server running which is MASTER for all zonesthat we have.

For 724 domains that we have, I have added 2 new pdns servers (going 
from 8 to 10 pdns nameservers). Via a batch script I inserted a total of 
2*724 NS records to add those new pdns servers. The script was done 
adding those records before the pdns MASTER noticed the serial updates, 
so for all those 724 domains it started generating notifications in one 
batch.

After some time things calm down in /var/log/syslog and I assume pdns is 
done with all its transfers.

When doing a count of domains and records on the pdns servers that 
should have the same database contents, I get the following results:

             domains records
pdns01          724   40783
pdns02          724   40783
pdns03          724   40784
pdns04          724   40297
pdns05          724   39701
pdns06          724   40777
pdns07          724   40781
pdns08          724   40783
pdns09           19     359
pdns10          317   12566

pdns09 and pdns10 are the new nameservers.

I've been walking into this issue a lot a and even have a script to 
workaround this issue.
I have a script that will notify each pdns server for every domain that 
it is authorative for. After each notification it will sleep for 0.1 
seconds. This is the workaround and will fix the issues. If I run it for 
pdns09:

pdns09          724   40784

So, should I increment threads on my MASTER?
I am running the following on my SUPERMASTER:
$ dpkg --list | grep pdns
ii  pdns-backend-mysql               3.0-1.1ubuntu1 generic MySQL 
backend for PowerDNS
ii  pdns-server                      3.0-1.1ubuntu1 extremely powerful 
and versatile nameserver

$ pdns_control version
3.0

$ lsb_release -rd
Description:    Ubuntu 12.04.2 LTS
Release:    12.04

With the following configuration:
   allow-recursion=127.0.0.1
   config-dir=/etc/powerdns
   daemon=yes
   guardian=yes
   lazy-recursion=yes
   module-dir=/usr/lib/powerdns
   setgid=pdns
   setuid=pdns
   socket-dir=/var/run
   version-string=powerdns
   local-address=0.0.0.0
   local-port=53
   launch=gmysql
   gmysql-socket=/var/run/mysqld/mysqld.sock
   gmysql-user=pdns_user
   gmysql-dbname=pdns_db
   gmysql-password=****
   disable-axfr=no
   master=yes
   slave=yes
   receiver-threads=2

pdns09: runs the same OS + Package version.
configuration:
   config-dir=/etc/powerdns
   daemon=yes
   disable-axfr=yes
   guardian=yes
   lazy-recursion=yes
   local-address=1.2.3.4
   local-port=53
   module-dir=/usr/lib/powerdns
   setgid=pdns
   setuid=pdns
   socket-dir=/var/run
   version-string=powerdns
   include=/etc/powerdns/pdns.d
   slave=yes
   receiver-threads=2
   allow-recursion=127.0.0.1, 1.2.3.0/24
   recursor=127.0.0.1

Does anybody know if I can fix the issues I'm having? Or that I'm just 
asking too much of my setup and should pipe it down a bit. I understand 
that 10*724 zone transfers at once may simply ask way too much from pdns...

Kind regards,
Tom van leeuwen