BIND backend reports unknown type 'secondary' but doesn't report unknown keyword 'primaries'

[jpmens]

• Program: Authoritative
• Issue type: Bug report

Short description

PowerDNS Authoritative with the BIND backend correctly reports a zone type secondary as unknown, but it doesn't complain about missing primary servers when the secondary (slave) zone is configured with primaries instead of masters.

$ cat named.conf
zone "a1.dnslab.org" IN {
	type secondary;
	primaries { 192.0.2.1; };
	file "/etc/pdns/a1";
};

Environment

• Operating system: CentOS Linux 8
• Software version: 4.7.0-alpha0.192.master.g3f4b183ea
• Software source: repo.powerdns.com

Steps to reproduce

1. Configure pdns.conf

   bind-config=/etc/pdns/named.conf
   daemon=no
   disable-axfr=no
   disable-syslog=yes
   guardian=no
   launch=bind
   log-dns-details=yes
   master=no
   secondary=yes
   setgid=pdns
   setuid=pdns
   slave=yes
   

2. Configure named.conf

   zone "a1.dnslab.org" IN {
   	type secondary;
   	primaries { 192.0.2.1; };
   	file "/etc/pdns/a1";
   };
   

3. Launch PowerDNS

   # pdns_server
   Jan 13 12:53:40 [bindbackend] Parsing 1 domain(s), will report when done
   Jan 13 12:53:40 [bindbackend] Warning! Skipping zone 'a1.dnslab.org' because type 'secondary' is invalid
   Jan 13 12:53:40 [bindbackend] Done parsing domains, 1 rejected, 0 new, 0 removed
   

4. Replace secondary by slave in named.conf
5. Launch

   # pdns_server
   Jan 13 13:05:26 [bindbackend] Parsing 1 domain(s), will report when done
   Jan 13 13:05:26 [bindbackend] error at 2022-01-13 13:05:26 +0000 no file found for new slave domain 'a1.dnslab.org'. Has not been AXFR'd yet
   Jan 13 13:05:26 [bindbackend] Done parsing domains, 1 rejected, 1 new, 0 removed
   

6. Replace primaries by masters in named.conf
7. Launch

   # pdns_server
   Jan 13 13:06:13 [bindbackend] Parsing 1 domain(s), will report when done
   Jan 13 13:06:13 [bindbackend] error at 2022-01-13 13:06:13 +0000 no file found for new slave domain 'a1.dnslab.org'. Has not been AXFR'd yet
   Jan 13 13:06:13 [bindbackend] Done parsing domains, 1 rejected, 1 new, 0 removed
   ...
   Jan 13 13:06:13 Zone 'a1.dnslab.org' (/etc/pdns/a1) reloaded
   Jan 13 13:06:13 AXFR-in zone: 'a1.dnslab.org', primary: '137.184.55.191', zone committed with serial 3
   

Expected behaviour

I expected PowerDNS to report that the word primaries is unknown or that there are no primaries/masters configured for the secondary zone.

Actual behaviour

No diagnostic message, and no transfer of the secondary zone.

[Habbie]

I believe we ignore unknown commands inside zone { } and we simply do not recognise primaries yet.