Module 6: Managing and Monitoring Domain Name System (DNS)

Overview Configuring the Time-to-Live Value Configuring Aging and Scavenging Integrating DNS with WINS Testing the DNS Server Configuration Verifying that a Resource Record Exists by Using Nslookup, DNSCmd, and DNSLint Monitoring DNS Server Performance

Lesson: Configuring the Time-to-Live Value How the Time-to-Live Value Works How to Configure the Time-to-Live Value

How the Time-to-Live Value Works The records in the zone are sent to other DNS servers and clients in response to queries 1 1 DNS servers and DNS clients that store the record in their cache hold the record for the TTL period supplied in the record 2 2 When the TTL expires, the record is removed from the cache 3 3 The Time-to-Live (TTL) value is a time-out value expressed in seconds that is included with DNS records that are returned in a DNS query Zone TTL set on the zone DNS Server1 DNS Client Authoritative DNS Server2 Authoritative DNS Server2 Cache Resource Record

How to Configure the Time-to-Live Value Your instructor will demonstrate how to: Adjust the TTL value for a zone Adjust the TTL value for a resource record Adjust the TTL value for a zone Adjust the TTL value for a resource record

Practice: Configuring the Time-to-Live Value In this practice, you will configure the TTL value

Lesson: Configuring Aging and Scavenging What Are Aging and Scavenging Parameters? How Aging and Scavenging Work How to Configure Aging and Scavenging

What Are Aging and Scavenging Parameters? ParameterDescriptionExample No Refresh Interval The time period when the DNS server does not accept refresh attempts 7-days (default) Refresh Interval The time period when the DNS server does accept refresh attempts 7-days (default) Aging is the process that determines whether a stale DNS resource record should be removed from the DNS database Scavenging is the process of cleaning and removing outdated or extinct names data from the WINS database A refresh attempt is the process of a computer requesting a refresh on its DNS record

How Aging and Scavenging Works Jan 1Jan 15Jan 8 Scavenge No-Refresh interval No-Refresh interval Refresh interval Refresh interval Time stamped Time stamped Aging 7-days

How to Configure Aging and Scavenging Your instructor will demonstrate how to: Set aging/scavenging parameters for the DNS server Set aging/scavenging parameters on a DNS zone Enable automatic scavenging of stale resource records on a DNS server Start immediate scavenging of stale resource records View when a zone can start scavenging stale resource records Configure the time stamp on a DNS resource record View the time stamp on a dynamic resource record Set aging/scavenging parameters for the DNS server Set aging/scavenging parameters on a DNS zone Enable automatic scavenging of stale resource records on a DNS server Start immediate scavenging of stale resource records View when a zone can start scavenging stale resource records Configure the time stamp on a DNS resource record View the time stamp on a dynamic resource record

Practice: Configure Aging and Scavenging In this practice, you will configure aging and scavenging

Lesson: Integrating DNS and WINS Multimedia: DNS and WINS Integration How to Integrate DNS with WINS

Multimedia: DNS and WINS Integration The objective of this presentation is to explain how DNS and WINS can be integrated in the network infrastructure At the end of this presentation, you will be able to:  Define DNS and WINS integration  Explain how host names and NetBIOS names fit into DNS and WINS integration  Describe how DNS and WINS integration works

How to Integrate DNS with WINS Your instructor will demonstrate how to integrate DNS with WINS

Practice: Integrating DNS with WINS In this practice, you will integrate DNS with WINS

Lesson: Testing the DNS Server Configuration How Simple and Recursive Queries Work How to Test the DNS Server Configuration

How Simple and Recursive Queries Work A simple query is a query that performs a local test by using the DNS client to query the DNS server A recursive query is a query that tests a DNS server by forwarding a recursive query to another DNS server DNS Server DNS Service Authoritative zone: training.nwtraders.msft DNS Client Resolver DNS Root Server

How to Test the DNS Server Configuration Your instructor will demonstrate how to: Manually test a simple query on the DNS server Manually test a recursive query on the DNS server Enable automatic query testing on the DNS server Manually test a simple query on the DNS server Manually test a recursive query on the DNS server Enable automatic query testing on the DNS server

Practice: Testing the DNS Server Configuration In this practice, you will test the DNS server configuration

Lesson: Verifying that a Resource Record Exists by Using Nslookup, DNSCmd, and DNSLint Why Verify that a Resource Record Exists? Nslookup DNSCmd DNSLint How to Verify that a Resource Record Exists by Using Nslookup, DNSCmd, and DNSLint

Why Verify that a Resource Record Exists? To identify issues with your DNS solution, you can verify: Missing records Incomplete records Incorrectly configured records Missing records Incomplete records Incorrectly configured records You can use the following three utilities to monitor DNS: Nslookup DNSCmd DNSLint Nslookup DNSCmd DNSLint

Nslookup Nslookup is a command-line utility used to diagnose DNS infrastructure

DNSCmd DNSCmd is a DNS support tool which allows you to complete many DNS administrative tasks on the DNS server from a command prompt

DNSLint DNSLint is a Microsoft Windows utility that can run a series of queries to help diagnose common DNS name resolution issues

How to Verify that a Resource Record Exists by Using Nslookup, DNSCmd, and DNSLint Your instructor will demonstrate how to: Verify that a resource record exists in DNS by using Nslookup Install DNSCmd Display a complete list of zones configured on a DNS server, by using DNSCmd Display information about a specific zone that is configured on a DNS server, by using the DNSCMD Create a DNSLint report Verify that a resource record exists in DNS by using Nslookup Install DNSCmd Display a complete list of zones configured on a DNS server, by using DNSCmd Display information about a specific zone that is configured on a DNS server, by using the DNSCMD Create a DNSLint report

Practice: Verifying that a Resource Record Exists by Using Nslookup, DNSCmd, and DNSLint In this practice, you will verify that a resource record exists by using Nslookup, DNSCmd, and DNSLint

Lesson: Monitoring DNS Server Performance Guidelines for Monitoring DNS Server Performance by Using the Performance Console What Is a DNS Event Log? What Is DNS Debug Logging? How to Monitor DNS Server Performance by Using Logging

Guidelines for Monitoring DNS Server Performance by Using the Performance Console Performance counter What to look for after a baseline is established Dynamic Update Rejected Any increase over the baseline may be cause for further investigation Recursive Queries/sec If this counter goes dramatically up or down, then it should be further investigated AXFR Request Sent If this counter goes dramatically above the baseline, then it could reflect a need to review the number of changes in the zone and the configuration of zone transfers

What Is a DNS Event Log? A DNS event log is a system log configured to log only DNS events

What Is DNS Debug Logging? Primary DNS Server1 DNS debug logging is an optional logging tool for DNS that stores the DNS information that you select Secondary DNS Server2

How to Monitor DNS Server Performance by Using Logging Your instructor will demonstrate how to: Enable and configure debug logging options on the DNS server View a DNS server debug log file View the DNS server event log located on another computer Enable and configure debug logging options on the DNS server View a DNS server debug log file View the DNS server event log located on another computer

Practice: Monitoring DNS Server Performance In this practice, you will monitor DNS server performance

Lab A: Managing and Monitoring DNS In this lab, you will manage and monitor DNS