Domain name policy for .no
Appendix F: Technical name server requirements

This document describes technical requirements for DNS registration, in other words, the requirements that must be fulfilled by domains registered by Norid. It is assumed that the registrar has the necessary technical competence to understand these requirements.

Norid will check domains against these requirements at the time of registration and afterwards at regular intervals. Failure to comply with these requirements may result in rejection of the application or deletion of the domain.

The following requirements apply to domains to be registered by Norid:

1. At least two separate name servers
   Every domain must be served by at least two separate name servers, which run on physically separate machines.

2. Consistency between data in the domain name application and response from name servers
   The response from the name servers specified for a domain must include the same name servers as those specified in the application. Note that both the names and the number of name servers must be the same.

3. Authoritative name servers
   All the name servers specified for a domain must respond authoritatively for the domain.

4. Accessible name servers
   Name servers must be permanently connected to the Internet, and must have a permanently assigned (fixed) IP address.

5. Correct e-mail information in the SOA (Start Of Authority) record
   The SOA record for a domain must include a functioning E-mail address for the administrator responsible for the operation of the name server.

6. Consistent serial number in the SOA record
   The serial number in the SOA record must be the same for all the specified name servers.

7. Canonical name on the right-hand side in NS and MX records
   On the right-hand side in an NS record the canonical name must always be used, and not an alias (CNAME).

   On the right-hand side in an MX record the canonical name must always be used, and not an alias (CNAME). The requirement for the canonical name in the MX record can be waived if the specified contact persons for a domain have e-mail addresses outside the domain.