NETWORK CONFIGURATION

Ensuring DNS resolves in NRPC -- Best practices
The following procedures provide the best name-resolution practices for an IBM® Lotus® Domino™ server using the default NRPC configuration on a TCP/IP network (one IBM® Lotus® Notes® network port for TCP/IP). These procedures address the following DNS configurations:
If your TCP/IP configuration has multiple Notes network ports for TCP/IP, see the topic Ensuring DNS resolves in advanced TCP/IP configurations.

When you have one DNS domain
If your company uses only one DNS domain, doing the following eliminates the need for CNAME records in DNS:

1. Assign the same name as both the Domino server common name and the simple IP host name registered with DNS.

2. Make sure the Net Address field on the Server document contains the server's FQDN.

3. Create an A record (or, for IPv6, AAAA record) in DNS.

For example, you set up the Domino server App01/Engr/Acme. Thus, you register the server with DNS as app01, the server's common name. The Net Address field in the Server document contains app01.acme.com (the server's FQDN), and the A record is: app01.acme.com IN A 192.168.10.17.

When you have multiple DNS domain levels
If your company uses multiple DNS domain levels -- for example, when each country in which a multinational company has offices is a subdomain in DNS -- doing the following eliminates the need for multiple CNAME records in DNS and ensures that DNS lookups always work, regardless of the DNS domain level of the user's system:

1. Assign the same name as both the Domino server common name and the simple IP host name.

2. Make sure the Net Address field on the Server document contains the server's FQDN.

3. Create an A record (or, for IPv6, AAAA record) in DNS.

4. If users' systems are in a different DNS domain than that of their home server or in a DNS subdomain of their home server's domain, set up a secondary name server. Place this secondary name server on the same physical network as the users' systems or on a network that the users can access.


5. Set up all Notes users or a subset of users affected by Step 4, or set up an individual Notes user.

For example, you register the Domino server ParisMail01/Sales/Acme with DNS as parismail01.france.acme.com. Parismail01 is the home server for some users in the DNS subdomain spain.acme.com. You set up a secondary name server, Nameserver/Acme, register it with DNS as nameserver.acme.com, and ensure that the Location documents of users who need a secondary name server point to this server.

When a user in spain.acme.com attempts a first connection with the home server (parismail01.france.acme.com), the connection fails because the DNS subdomain for spain.acme.com has no records for the subdomain france.acme.com. Notes then connects successfully with the secondary name server (nameserver.acme.com), since the DNS subdomain for spain.acme.com does include the records for acme.com. When the secondary name server supplies the Notes workstation with the FQDN from the Net Address field in the Server document for ParisMail01, DNS resolves the FQDN to an IP address, and the user can access mail.

As long as all Server documents in the Domino domain have the TCP/IP network address in FQDN format, this approach allows any Notes workstation or Domino server to locate any Domino server, regardless of its DNS domain level.

See also