HP-UX IP Address and Client Management Administrator's Guide HP-UX 11i v2, HP-UX 11i v3

Choosing Master Servers and Slave Servers
Follow these guidelines while selecting a master server and slave server:
• You must have at least two master servers per domain: a primary master and one or more
slaves for redundancy. You can configure one host as a master for multiple domains (primary
for some domains and secondary for other domains).
• You must choose hosts that are as independent as possible for redundancy. For example,
choose hosts that use different power sources or cables.
• You must choose hosts that have the most reliable Internet connectivity with the best gateway
connections.
• Name servers for a particular zone need not physically reside within the same domain. In
general, zones are more accessible to the rest of the Internet if their name servers are widely
distributed, instead of on the premises of the organization that manages the domain.
Types of Resource Records
Resource records (RRs) are entries in the data files in a name server. Typically, a resource record
is of the following format:
name ttl
class type data
Where:
name
Specifies the domain name where the RRs are found
ttl
Specifies the time after which a resource record becomes inactive
class
Specifies an encoded 16-bit value that identifies a protocol family or an instance of a
protocol
type
Specifies an encoded 16-bit value that specifies the resource record type
data
Specifies the resource data. The format of the data is specific to the type and class of
the resource record.
Following is a sample resource record:
. 3600000 IN
NS A.ROOT-SERVERS.NET.
Table 2-1 lists the different types of resource records in BIND.
Table 2-1 BIND Resource Records
DescriptionName
Specifies the global position. The GPOS record must be superseded by the LOC record.Global Position (GPOS)
Specifies the geographic location of the service. LOC enables DNS to carry location
information about hosts, networks, and subnets. The LOC record supersedes the
GPOS record.
Location Information (LOC)
Provides rules for mapping certain parts of uniform resource identifiers (URIs) to
domain names. By changing the mapping rules, the host that is contacted to resolve
a URI can be changed.
Naming Authority Pointer
(NAPTR)
Maps a domain name to an OSI network service access point address as described
in RFC 1706 (The Naming Authority Pointer (NAPTR) DNS Resource Record). NSAP
to name translation is accomplished using the PTR RR as described in RFC 1035
(Domain Names - Implementation and Specification). The PTR RR can be used with
any NSAP address format.
Network Service Access Point
(NSAP)
Maps between RFC 822 (Standard for the format of ARPA Internet text) and X.400
addresses.
Mail Mapping Information
(PX)
Specifies the responsible person for a domain.
Responsible Person (RP)
Choosing Name Servers for Your Domain 65