[nsd-users] solved: delayed zone transfers (was: NSD 4.1.14 release)

[A. Schulze]

W.C.A. Wijngaards:

Hello Wouter,

> NSD tries the masters in the order you listed them in the config file.
> If you list all the IPv4 first, and it is an IPv6-only server, I
> guess that makes it slow.
yes, I arranged the master server list in a different order and nsd  
behave different.

> Because initially the network is down, it'll do exponential backoff on
> retries.  That explains the wait time.
>
> NSD actually throttles fetching the zones, and does not do that
> immediately after you start it.  It inserts short delays.

The two minutes for the first, cold start ¹) I mentioned, are a tcp_timeout!
Looks like (my?) nsd instance cannot axfr from  
b.root-servers.net[2001:500:84::b]
which happen to be the first in my list.
Changing the order again let nsd fetch the root zone immediately after  
a cold start.

Everything is fine now.

Thanks,
Andreas

¹) cold start
- no database file
- no zone file written to disk
- no xfrd.state file