.nl domains DNS requirements

There're few requirements for name servers for .nl domains:

The name servers registered with us must be in the domain's NS records.
The primary data source in the SOA record's MNAME field must be a valid host name.
The SOA record's MNAME field and the NS and MX records must refer to objects with A records (and possibly AAAA records).
- They mustn't refer to objects with CNAME records.
The SOA record's RNAME field must follow the syntax referred to in RFC 1912, section 2.2.
- It also has to provide a valid e-mail address that accepts mail.
The TTL value of the NS records must not be less than 3600 (1 hour).
- That prevents the .nl zone getting too much traffic if the records aren't configured correctly.
- We recommend a TTL value of 172800 (48 hours). That's because the records are important parts of the internet's infrastructure. It's also a lot of work to change them.
The expire value of the SOA record in the registered domain's zone file must be
between 604800 (7 days) and 3456000 (40 days).
- Our procedures assume a value in that range. The quarantine period for a cancelled domain name is based on that range, for example.
- The expire value has to be at least seven times the refresh value. Also, the retry value mustn't be higher than the refresh value.
For every name server host at a subdomain level within the .nl domain, there must be a glue record in the .nl zone file.
- o The record has to be type A or type AAAA.
If a name server is running on a host operated by the same registrar, the canonical hostname must be in the zone file.
- The zone file mustn't include an alias that's subordinate to the domain name itself. That's so that the .nl zone file doesn't get littered with unnecessary glue records. It also prevents problems if the IP address of the name server is changed.