First failure on ifurlup function

[dal13002]

Hi,
I know when using functions like ifurlup in Authoritative PowerDNS the first DNS lookup will fail. I notice queries after the first do work as expected as long as we keep querying. What I am seeing is after a while (ie hour) if no queries are sent, the server will again fail the query- acting like the very first query.

Is this normal behavior?

[Habbie]

Yes, the default value for lua-health-checks-expire-delay is 3600, but you can change it.