On Mon, Nov 02, 2020 at 02:41:18PM +0100, Roman Steinhart via Pdns-users wrote:
> Hi guys, > > We're running two PowerDNS authoritative instances v4.3.0/4.3.1 (upgraded > today) with a self-written remote backend. > > From time to time we see small, 1-2 minute long spikes of servfail > responses. > In these timeframes one-third of all responses sent by PowerDNS are > servfail responses, the other two-thirds are successful. > https://img.steinh.art/1e7J10Qu.png > - These spikes typically occur two or three times a day, at different times > the day on both DNS servers. > - There is no relation to the type of DNS records being queried. It affects > any type e.g. A, AAAA, SRV, etc. I don't how much PDNS relies on the remote > backend in online signing mode, but the problem also occurs with DS records. > - It's not related to the query name. I can query a name with the same name > as 10 minutes later and it's working fine. > - There are no spikes in other server metrics like CPU, memory, etc. > > Luckily PowerDNS is logging why these servfails occur: > > > Exception building answer packet for britishgerbil.aternos.me/DS (Attempt > > to print an unset dnsname) sending out servfail > > But unfortunately, I don't have any clue what this means. > > I also checked our remote backend of course and everything looks fine there. > I don't know if my assumption is correct, but the fact that DS records are > generated by PDNS (in online signing mode) and are affected too I would say > that it's not related to the remote backend? > > Maybe someone of you has a hot hint for me or can explain what that error > message tries to tell me :) > > Thanks in advance. > > ~ Roman > _______________________________________________ > Pdns-users mailing list > Pdns-users@mailman.powerdns.com > https://mailman.powerdns.com/mailman/listinfo/pdns-users The issues is that some code tried to do a toString() on a an non-set DNSName. This *can* be due to a backend doing something wrong. I suspect that on irc there are people capable of helping you debugging this, -Otto _______________________________________________ Pdns-users mailing list Pdns-users@mailman.powerdns.com https://mailman.powerdns.com/mailman/listinfo/pdns-users
