Creating DNS Computer Names

Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2

It is important to develop a practical DNS computer naming convention for your network. This enables users to remember the names of computers on public and private networks easily, and therefore facilitates access to resources on your network.

The DNS computer name creation process varies according to whether you are creating a new DNS infrastructure, integrating your DNS infrastructure with an existing third-party infrastructure, or upgrading an existing DNS infrastructure.

Creating Computer Names in a New Windows Server 2003 DNS Infrastructure

Use the following guidelines when creating names for the DNS computers in your new Windows Server 2003 DNS infrastructure:

  • Select computer names that are easy for users to remember.

  • Identify the owner of a computer in the computer name. For example, john-doe-1 indicates that John Doe uses the computer.

  • Select names that describe the purpose of the computer. For example, a file server named past-accounts-1 indicates that the file server stores information related to past accounts.

  • Do not use character case to convey the owner or purpose of a computer. DNS is not case-sensitive.

  • If you are deploying DNS to support Active Directory, match the Active Directory domain name to the primary DNS suffix of the computer name. For more information about designing the Active Directory logical structure, see "Designing the Active Directory Logical Structure" in Designing and Deploying Directory and Security Services of this kit.

  • Use unique names for all computers in your organization. Do not assign the same computer name to different computers in different DNS domains.

  • Use ASCII characters to ensure interoperability with computers running versions of Windows earlier than Windows 2000. For DNS computer names, use only the characters listed in RFC 1123:Requirements for Internet Hosts — Application and Support, which include A–Z, a–z, 0–9, and the hyphen (-). Windows Server 2003 DNS supports almost any UTF-8 character in a name; however, do not use extended ASCII or UTF-8 characters unless all of the DNS servers in your environment support them.

Note

  • Windows Server 2003 DNS is configured to use UTF-8 name checking by default.

Creating Computer Names in an Integrated DNS Infrastructure

If you are integrating Windows Server 2003 DNS with an existing third-party DNS infrastructure, you do not need to make any changes to your third-party DNS host names. If you are migrating to Windows Server 2003 DNS from a third-party DNS infrastructure, you must ensure that the host names that are used in the third-party DNS infrastructure conform to the DNS Internet naming standards.

If you are integrating or migrating an existing public DNS infrastructure that is connected to the Internet into your existing DNS infrastructure, you do not need to make any changes to the DNS domain names of your infrastructure.

Creating Computer Names When Upgrading a DNS Infrastructure

If you are upgrading to Windows Server 2003 DNS from Windows NT 4.0, you do not need to change your DNS host names; however, you might need to convert any NetBIOS names to DNS names. DNS names must conform to the DNS standard defined by RFC 1123.

Table 3.7 lists the different character sets that are supported by standard DNS, Windows Server 2003 DNS, and NetBIOS.

Table 3.7   Character Set Restrictions

Character Set Restriction Standard DNS (Including Windows NT 4.0) DNS in Windows 2000 and Windows Server 2003 NetBIOS

Characters permitted

Supports RFC 1123, which permits A–Z, a–z, 0–9, and the hyphen (-).

Supports RFC 1123 and UTF-8. On a per-server basis, You can configure the Windows 2000 DNS Server service to allow or disallow the use of UTF-8 characters on your DNS server.

Not allowed: Unicode characters, numbers, white space, symbols: / \ [ ] : | < > + = ; , ? and *)

Maximum host name and FQDN length.

63 octets per label. 255 bytes per FQDN (254 bytes for the FQDN plus one byte for the terminating dot).

The same as standard DNS with the addition of UTF-8 support. Character count is insufficient to determine size because some UTF-8 characters exceed one octet in length. Domain controllers are limited to 155 bytes for an FQDN.

16 bytes in length.

Important

  • Names encoded in UTF-8 format must not exceed the limits defined in RFC 2181: Clarifications to the DNS Specification, which specifies a maximum of 63 octets per label and 255 octets per name.