Microsoft windows 2000 DNS manual Name Server Resolver Root-server Gov Whitehouse.gov

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or a successful response. Resolvers typically make recursive queries. With a recursive query, the DNS server must contact any other DNS servers it needs to resolve the request. When it receives a successful response from the other DNS Server(s), it then sends a response to the client. The recursive query is typical for a resolver querying a name server and for a name server querying its forwarder (another name server configured to handle requests forwarded to it).

When a DNS server processes a recursive query and a query can not be resolved from local zone files, the query must be escalated to a root DNS server. Each standards-based implementation of DNS includes a cache file (or root server hints) that contains entries for Root Servers of the Internet domains. The latest version of the named cache file can be downloaded from InterNIC at ftp://rs.internic.net/domain/named.cache.

An iterative query is one in which the name server is expected to provide the best information (also known as referral if the server is not authoritative for the name) based on what the server knows from local zone files or from caching. If a name server doesn’t have any information to answer the query, it simply sends a negative response. A non-forwarding DNS server makes this type of query as it tries to find names outside its local domain(s). It may have to query a number of outside DNS Servers in an attempt to resolve the name.

The following figure shows an example of both types of queries.

Name Server

1 8

Resolver

 

2

 

 

""

 

 

3

 

 

 

 

 

Name Server

 

4

 

 

 

 

 

(root-server)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

gov

 

 

 

 

 

 

 

 

5

 

 

 

 

 

 

 

 

 

 

 

Name Server

 

6

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

whitehouse.gov

 

 

 

 

 

 

 

7

 

 

 

 

 

 

 

 

 

 

 

Name Server

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

iterative queries

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

recursive query

 

 

 

 

 

 

 

 

 

 

 

client asks for IP

 

 

 

address for

 

 

 

www.whitehouse.gov

gov

whitehouse

www

In the provided example the following queries are used to determine IP address for

Windows 2000 White Paper

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Contents Windows 2000 DNS Microsoft Corporation. All rights reserved Contents Designing a DNS Namespace for the Active Directory Summary Page DNS Fundamentals Standards and Additional Reading Name Services in WindowsDraft-skwan-gss-tsig-04.txt GSS Algorithm for Tsig GSS-TSIG History of DNSHierarchy of DNS Domain Names Structure of DNSDNS and Internet Int/net/orgCom Edu Gov Mil Army Microsoft Mit MydomainDistributing the Database Zone Files and Delegation TTLMicrosoft My domain ftp Ntserver Replicating the DNS databaseQuerying the Database NEW Features of the Windows 2000 DNSName Server Resolver Root-server Gov Whitehouse.gov Time to Live for Resource Records Updating the DNS DatabaseActive Directory Storage and Replication Integration Active Directory Service Storage ModelWindows 2000 White Paper Controlling Access to Zones Replication ModelZone Type Conversions Protocol Description Incremental Zone TransferSlave DNS Server Ixfr and DS Integration Dynamic UpdateZone Log File Master DNS ServerDynamic Update of DNS Records Update AlgorithmDhcp Client Mixed EnvironmentClient Reregistration Statically Configured ClientSecure Dynamic Update RAS ClientEstablishing a security context by passing security tokens Secure Dynamic Update Policy Controlling Update Access to Zones and Names DnsUpdateProxy GroupAging and Scavenging DNS Admins GroupAging and Scavenging Parameters DefaultEnableScavenging Scavenging Period DescriptionRecord Life Span Scavenging Algorithm Configuring Scavenging ParametersInteroperability Considerations Unicode Character SupportDomain Locator Finish IP/DNS Compatible Locator DNS Record Registration and Resolver RequirementsLdap.tcp.dc.msdcs.DnsDomainName Kerberos.tcp.dc.msdcs.DnsDomainName IP/DNS DC Locator Algorithm Finish Discovering Site specific DCsCaching Resolver Fully-Qualified Query Name ResolutionUnqualified Single-Label Query Using Global Suffix Search OrderUnqualified Multi-Label Query Using Primary and Per-adapter Domain NamesUnqualified Single-Label Query Scenarios Name Resolution ScenariosNegative Caching Fully-Qualified Query ScenariosMicrosoft Implementation of Negative Caching DNS Server List ManagementAdministrative Tools WMI Support for DNS Server AdministrationDNS Manager Interoperability Issues Using Wins and Winsr RecordsUsing UTF-8 Characters Format DNS Server Performance Receiving Non-RFC Compliant DataUtilization Hardware components Sizing Server Capacity PlanningChoosing Names Internet Access ConsiderationsWindows 2000 White Paper Windows 2000 White Paper Windows 2000 White Paper VPN Com Yyy.com Zzz.com Windows 2000 White Paper Primary Zone YYY corporation ZZZ corporation VPN Firewall Computer Names Characters in NamesPer-Adapter Naming Full computer nameIntegrating ADS with Existing DNS Structure Domain name and sites. Active Directory domain name DNS Migration to Windows 2000 DNSPartitioning, and Replication Choosing your Zones Deploying DNS to Support Active DirectoryWins Referral Using Automatic ConfigurationIxfr Ixfr For More InformationWindows 2000 White Paper