MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration Chapter 6 Managing and Administering DNS in Windows Server 2008

Objectives Describe and install Active Directory Domain Services Manage your Domain Name System (DNS) environment Troubleshoot your DNS environment Manage Windows Internet Name Service Describe the new features of DNS in Windows Server 2008 MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 2

Introduction to Active Directory Domain Services Active Directory (AD) clients –Use DNS to locate all the resources available on the network DNS servers you can run in an AD DS environment –Standard DNS servers –AD DS–integrated DNS servers MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 3

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Using AD DS AD DS –Microsoft’s implementation of a directory services infrastructure –Stores attributes, or specific information, for objects within a network MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 5

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Using AD DS (continued) Domain controller locator –Runs at logon to provide client with location of a DC that can authenticate its requests AD domain names –Every AD domain in Windows Server 2008 has a naming convention based on a DNS domain name DNS requirements for AD –When a DC is added to a domain, SRV and A records are created to allow clients to find a DC during logon MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 7

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AD-Integrated DNS Benefits of AD DNS –Faster and more efficient replication –Database security –Multimaster support for updates and replication Administrators can choose one of the following zone replication options for AD DS DNS zones –To all DNS servers in this forest –To all DNS servers in this domain –To all domain controllers in this domain (for Windows 2000 compatibility) MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 9

DNS Zone Layout AD DS site structure –AD DS sites are designed to limit the replication traffic across wide area network (WAN) links Distribution of an IT department –How your network is administered helps determine the layout for your DNS zones and servers Forwarding –Types: standard and conditional MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 10

MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 11

Dynamic DNS Allows supported DNS clients to dynamically update their DNS records on a DNS server Allows DNS clients to update their A, AAAA, and PTR records Deletes records of clients removed from the domain or whose DHCP leases expire Scavenging –Process within a DNS database that uses time stamps to determine when records can update themselves MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 12

MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 13

Dynamic DNS (continued) DHCP configuration –By default, DHCP is configured to provide dynamic updates to clients that support this feature DNS configuration –Dynamic updates are configured at the DNS zone level Secure and nonsecure updates –Secure: Performed only by an authenticated client –Nonsecure: Performed by any client MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 14

Dynamic DNS (continued) How clients use DNS in an Active Directory environment –Failure to point your client to internal DNS servers can cause problems DNS Client Group Policy settings –For environments that do not use DHCP or have statically assigned IP addresses, this is a good option for defining DNS suffixes and search orders MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 15

MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 16

Managing DNS DNS console –Main GUI tool used for configuring DNS –Provides access to all DNS zones available on a server, along with configuration settings for the DNS role DNS Manager –Allows you to add DNS servers MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 17

Configuration Settings in the DNS Console DNS server level –Configuration and maintenance tasks you can perform Configure a DNS server Create the default application (Directory Partitions) Create a zone Set aging/scavenging for all zones Scavenge stale resource records MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 18

Configuration Settings in the DNS Console (continued) DNS zone level –Level where all DNS zones exist DNS record level –Modifying and deleting records –Defining security settings on a DNS record –Managing scavenging settings for a record –Setting record Time to Live MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 19

Round-Robin DNS Allows an administrator to configure load balancing of servers based on DNS name resolution information DNScmd –Can be used to disable or enable round-robin DNS along with other DNS features MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 20

Conditional Forwarding Forwarding based on a specific domain name Created in their own location under your server in the DNS console MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 21

Conditional Forwarding (continued) DNScmd –Command-line tool for performing configuration and maintenance tasks on a DNS server –Can be used to: Create and delete DNS zones Add and delete View information about DNS zones and records Change the zone type MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 22

Troubleshooting DNS DNS server logs –Global Logs folder: contains a subset of the event logs relating specifically to DNS called DNS Events –General Tab: DNS Events log file is set to a default size of 16,384 KB –Filter Tab: allows you to modify the view of the DNS Server log for better analysis of events MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 23

Command-Line Utilities Ping –You can ping a server by host name or FQDN Ipconfig –Commands and switches: ipconfig /all, ipconfig /flushdns, ipconfig /displaydns, ipconfig /registerdns DCDiag –Allows you to perform diagnostic queries of your DCs Nslookup –Allows you to perform detailed queries for DNS information from the command line MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 24

Command-Line Utilities (continued) Nslookup –Noninteractive - allows you to perform a single query from the command line by entering all of the query parameters at once –Interactive - allows you to launch nslookup in a command-line shell where you can define parameters one by one –Used with debug parameter; provides more detailed information MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 25

MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 26

MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 27

MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 28

Command-Line Utilities (continued) Debug log –Windows Server 2008 allows you to turn on debug logging for a DNS server –Allows you to capture packet data related to the DNS server functionality MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 29

MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 30

WINS Microsoft’s technology for resolving NetBIOS names to IP addresses Based on two important pieces –The Server service and the Client service WINS server service –Responsible for maintaining the WINS database and responding to WINS requests The WINS client service –Responsible for initiating WINS queries, client registration, and name renewal MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 31

WINS (continued) Global name zones (GNZs) –Provide single name–to–IP address resolution by creating CNAME records in a special GNZ –If a GNZ is created, a DNS server looks to the GNZ first and then to WINS MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 32

New DNS Features DNS on Server Core –You can deploy a single or multirole server running DNS and other services Support for IPv6 –Windows Server 2008 DNS supports the IPv6 address numbering scheme along with the AAAA resource records Primary Read-Only Zone –Read-only domain controllers (RODCs): contain a copy of the AD DS database and can answer client requests MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 33

New DNS Features (continued) Link-local multicast name resolution –Clients exchange simple messages to verify that they have a unique name on the local subnet DNS client changes –Clients periodically perform a check to ensure that they are authenticating with a local DC –Clients use LLMNR to resolve names on a local network segment when a DNS server is not available MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 34

New DNS Features (continued) Background zone loading –Allows DNS server to handle client requests immediately instead of waiting until the entire DNS zone is loaded GNZ –Allows you to host computer name–to–IP address resolution records in their Windows Server 2008 DNS zone MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 35

Summary In an AD DS environment, you can run two types of DNS servers –Standard DNS servers and AD DS DNS–integrated servers AD DS –Uses DCs to store all the AD objects and information about an environment –Uses a database structure to maintain its objects AD –Requires DNS for locating DCs, or the DC locator function MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 36

Summary (continued) Windows Server 2008 DNS implementations support two types of forwarding –Standard and conditional Dynamic DNS –Allows supported DNS clients to dynamically update their DNS records on a DNS server DNS console –Main GUI tool used for managing DNS MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 37

Summary (continued) You can configure DNS at the DNS server, zone, or record level During forwarding –DNS server sends queries made for DNS zones that do not match its own zone and cache information to another internal or external DNS server Troubleshoot DNS when –Your clients are having difficulties connecting to applications or resources MCTS Guide to Microsoft Windows Server 2008 Network Infrastructure Configuration 38