[Pdns-users] Strange behaviour of recursor cache on a particular domain

[bert hubert]

On Wed, Jun 14, 2006 at 05:11:11PM +0200, GAVARRET, David wrote:
> But my recursors don't have the same informations. Some still have the
> previous A record value (195.6.210.105), some others have both the old
> and the new one ... but they all give the same (and the last) serial
> number for the SOA :

Recursors don't really know about 'zones', so the SOA serial number is not
relevant for the powerdns recursor, nor are in this case the other.

I've tested changing an IP address and it does the right thing, except that
the old IP address lingers while expiring.

> ~$ dig +noall +answer @ns9 melusine.eu.org soa melusine.eu.org
> melusine.eu.org.        21600   IN      SOA     ns.melusine.eu.org.
> hostmaster.melusine.eu.org. 2006060701 7200 3600 1209600 259200
> melusine.eu.org.        115956  IN      A       195.6.210.105

Note that this is a (very) high number. It might simply be that
melusine.eu.org had a *huge* TTL, and is simply lingering.

Ah.. http://www.frameip.com/nntp/article-fr-comp-reseaux-ip.php?numero=27320

Arguably, PowerDNS should delete old data on receiving new data, but that
situation is not guaranteed, because it won't query anyhow until the TTL has
expired. Data can only be updated through additional records otherwise.

Does this help?

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