Microsoft windows 2000 DNS manual Aging and Scavenging Parameters

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•Which zones can be scavenged

•Which records must be scavenged if they become stale

The DNS server uses an algorithm that ensures that it does not accidentally scavenge a record that must remain, provided that you configure all the parameters correctly. By default, the scavenging mechanism is disabled. Do not enable it unless you are absolutely certain that you understand all the parameters. Otherwise, you might accidentally configure the server to delete records that it should retain. If a name is accidentally deleted, not only do users fail to resolve queries for that name, but also, any user can create that name in DNS and then take ownership of it, even on zones configured for secure dynamic update.

You can manually enable or disable aging and scavenging on a per-server, per- zone, or per-record basis. You can also enable aging for sets of records by using Dnscmd.exe. Keep in mind that if you enable scavenging on a record that is not dynamically updated, the record will be deleted if it is not periodically refreshed, and you must recreate the record if it is still needed.

If scavenging is disabled on a standard zone and you enable scavenging, the server does not scavenge records that existed before you enabled scavenging. The server does not scavenge those records even if you convert the zone to an Active Directory–integrated zone first. To enable scavenging of such records, use Dnscmd.exe.

Aging and Scavenging Parameters

The Windows 2000 DNS server uses a record timestamp, along with parameters that you configure, to determine when to scavenge records.

The table below lists the zone parameters that affect when records are scavenged. You configure these properties on the zone.

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 DNSCom Edu Gov Mil Army Microsoft Int/net/orgMit Mydomain DNS and InternetDistributing 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 Zone Type Conversions Controlling Access to ZonesReplication Model Protocol Description Incremental Zone TransferZone Log File Dynamic UpdateMaster DNS Server Slave DNS Server Ixfr and DS IntegrationDynamic Update of DNS Records Update AlgorithmDhcp Client Mixed EnvironmentSecure Dynamic Update Statically Configured ClientRAS Client Client ReregistrationEstablishing 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 ScenariosMicrosoft Implementation of Negative Caching Fully-Qualified Query ScenariosDNS Server List Management Negative CachingDNS Manager Administrative ToolsWMI Support for DNS Server Administration Using UTF-8 Characters Format Interoperability IssuesUsing Wins and Winsr Records Utilization DNS Server PerformanceReceiving Non-RFC Compliant Data 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