This document provides an overview of configuring and managing a DNS server, including:
1. Installing the DNS server role and configuring zones, records, and name resolution.
2. Describing DNS namespaces, zones, primary/secondary servers, and record types like SOA, NS, A, MX and SRV.
3. Explaining how DNS servers resolve queries using root hints, recursion, caching, and forwarders.
in this presentation their is the detailed information regarding Domain Name System that is DNS.
What is DNS,how it works,query, resolution wtc all are being covered thoroughly in this presentation as it would have in for all new upcoming Engineering students to know about the DNS as well as would also help employees to get the better understanding regarding the protocol.
The complete agenda of the presentation is to provide the detailed knowledge regarding dns as its the most basic protocol used in Web development.
Hope you would like it. If so please do like share and subscribe.
Overview of the Domain Name System (DNS).
In the early days of the Internet, hosts had a fixed IP address.
Reaching a host required to know its numeric IP address.
With the growing number of hosts this scheme became quickly awkward and difficult to use.
DNS was introduced to give hosts human readable names that would be translated into a numeric IP addresses on the fly when a requesting host tried to reach another host.
To facilitate a distributed administration of the domain names, a hierarchic scheme was introduced where responsibility to manage domain names is delegated to organizations which can further delegate management of sub-domains.
Due to its importance in the operation of the Internet, domain name servers are usually operated redundantly. The databases of both servers are periodically synchronized.
in this presentation their is the detailed information regarding Domain Name System that is DNS.
What is DNS,how it works,query, resolution wtc all are being covered thoroughly in this presentation as it would have in for all new upcoming Engineering students to know about the DNS as well as would also help employees to get the better understanding regarding the protocol.
The complete agenda of the presentation is to provide the detailed knowledge regarding dns as its the most basic protocol used in Web development.
Hope you would like it. If so please do like share and subscribe.
Overview of the Domain Name System (DNS).
In the early days of the Internet, hosts had a fixed IP address.
Reaching a host required to know its numeric IP address.
With the growing number of hosts this scheme became quickly awkward and difficult to use.
DNS was introduced to give hosts human readable names that would be translated into a numeric IP addresses on the fly when a requesting host tried to reach another host.
To facilitate a distributed administration of the domain names, a hierarchic scheme was introduced where responsibility to manage domain names is delegated to organizations which can further delegate management of sub-domains.
Due to its importance in the operation of the Internet, domain name servers are usually operated redundantly. The databases of both servers are periodically synchronized.
HBaseCon2017 Achieving HBase Multi-Tenancy with RegionServer Groups and Favor...HBaseCon
Achieving HBase Multi-Tenancy with RegionServer Groups and Favored Nodes
At Yahoo! HBase has been running as a hosted multi-tenant service since 2013. In a single HBase cluster we have around 30 tenants running various types of workloads (ie batch, near real-time, ad-hoc, etc). Typically such a deployment would cause tenant workloads to negatively affect each other because of resource contention (disk, cpu, network, cache thrashing, etc). Using RegionServer Groups we are able to designate a dedicated subset of RegionServers in a cluster to host only tables of a given tenant (HBASE-6721).
Most HBase deployments use HDFS as their distributed filesystem, which in turn does not guarantee that a region’s data is locally available to the hosting regionserver. This poses a problem when providing isolation since the hdfs data blocks may have to be read remotely from a different tenant’s host thus contending for disk or network resources. Favored nodes addresses this problem by providing hints to HDFS on which datanodes data should be stored and only assigns regions to these favored regionservers (HBASE-15531).
We will walk through these features explaining our motivation, how they work as well as our experiences running these multi-tenant clusters. These features will be available in Apache HBase 2.0.
by Francis Liu and Thiruvel Thirumoolan
https://youtu.be/xorEYNyLMbM
my compilation of the changes and differences of the upcoming 3.0 version of Hadoop. Present during the Meetup of the group https://www.meetup.com/Big-Data-Hadoop-Spark-NRW/
A Domain Name System assigns an alphabetic name to a numeric IP address and is made up of multiple Domain Name servers that enable IP address mapping for devices on the Internet (usually servers).
Updated version of my talk about Hadoop 3.0 with the newest community updates.
Talk given at the codecentric Meetup Berlin on 31.08.2017 and on Data2Day Meetup on 28.09.2017 in Heidelberg.
The current major release, Hadoop 2.0 offers several significant HDFS improvements including new append-pipeline, federation, wire compatibility, NameNode HA, Snapshots, and performance improvements. We describe how to take advantages of these new features and their benefits. We cover some architectural improvements in detail such as HA, Federation and Snapshots. The second half of the talk describes the current features that are under development for the next HDFS release. This includes much needed data management features such as backup and Disaster Recovery. We add support for different classes of storage devices such as SSDs and open interfaces such as NFS; together these extend HDFS as a more general storage system. Hadoop has recently been extended to run first-class on Windows which expands its enterprise reach and allows integration with the rich tool-set available on Windows. As with every release we will continue improvements to performance, diagnosability and manageability of HDFS. To conclude, we discuss the reliability, the state of HDFS adoption, and some of the misconceptions and myths about HDFS.
HBase has been in production in hundreds of clusters across the HDP customer base. In this talk, we will go over the best practices and lessons learned in supporting these clusters over the years. We will cover top 10 recurring issues like ZooKeeper, GC, number of regions, HBCK, operating system and coprocessor related issues and more across 1000+ support tickets. We will also cover common solutions and lessons learned and go into details of how to tune, monitor and operate your clusters. We will then cover some of the improvements that we have been adding to HBase and Ambari for easing up some of the pain.
HBaseCon2017 Achieving HBase Multi-Tenancy with RegionServer Groups and Favor...HBaseCon
Achieving HBase Multi-Tenancy with RegionServer Groups and Favored Nodes
At Yahoo! HBase has been running as a hosted multi-tenant service since 2013. In a single HBase cluster we have around 30 tenants running various types of workloads (ie batch, near real-time, ad-hoc, etc). Typically such a deployment would cause tenant workloads to negatively affect each other because of resource contention (disk, cpu, network, cache thrashing, etc). Using RegionServer Groups we are able to designate a dedicated subset of RegionServers in a cluster to host only tables of a given tenant (HBASE-6721).
Most HBase deployments use HDFS as their distributed filesystem, which in turn does not guarantee that a region’s data is locally available to the hosting regionserver. This poses a problem when providing isolation since the hdfs data blocks may have to be read remotely from a different tenant’s host thus contending for disk or network resources. Favored nodes addresses this problem by providing hints to HDFS on which datanodes data should be stored and only assigns regions to these favored regionservers (HBASE-15531).
We will walk through these features explaining our motivation, how they work as well as our experiences running these multi-tenant clusters. These features will be available in Apache HBase 2.0.
by Francis Liu and Thiruvel Thirumoolan
https://youtu.be/xorEYNyLMbM
my compilation of the changes and differences of the upcoming 3.0 version of Hadoop. Present during the Meetup of the group https://www.meetup.com/Big-Data-Hadoop-Spark-NRW/
A Domain Name System assigns an alphabetic name to a numeric IP address and is made up of multiple Domain Name servers that enable IP address mapping for devices on the Internet (usually servers).
Updated version of my talk about Hadoop 3.0 with the newest community updates.
Talk given at the codecentric Meetup Berlin on 31.08.2017 and on Data2Day Meetup on 28.09.2017 in Heidelberg.
The current major release, Hadoop 2.0 offers several significant HDFS improvements including new append-pipeline, federation, wire compatibility, NameNode HA, Snapshots, and performance improvements. We describe how to take advantages of these new features and their benefits. We cover some architectural improvements in detail such as HA, Federation and Snapshots. The second half of the talk describes the current features that are under development for the next HDFS release. This includes much needed data management features such as backup and Disaster Recovery. We add support for different classes of storage devices such as SSDs and open interfaces such as NFS; together these extend HDFS as a more general storage system. Hadoop has recently been extended to run first-class on Windows which expands its enterprise reach and allows integration with the rich tool-set available on Windows. As with every release we will continue improvements to performance, diagnosability and manageability of HDFS. To conclude, we discuss the reliability, the state of HDFS adoption, and some of the misconceptions and myths about HDFS.
HBase has been in production in hundreds of clusters across the HDP customer base. In this talk, we will go over the best practices and lessons learned in supporting these clusters over the years. We will cover top 10 recurring issues like ZooKeeper, GC, number of regions, HBCK, operating system and coprocessor related issues and more across 1000+ support tickets. We will also cover common solutions and lessons learned and go into details of how to tune, monitor and operate your clusters. We will then cover some of the improvements that we have been adding to HBase and Ambari for easing up some of the pain.
The Domain Name System (DNS) provides a way to map or translate an unfriendly numerical IP address into a people-friendly format. Although this translation isn’t mandatory, it does make the network much more useful and easy to work with for humans.
This Presentation explains about Domain Name System Records and Their Usage.
This explains DNS Records to New Beginners in an accurate manner. Get to learn live technology in an enhanced way only at Hackveda
Computer Networks Module 1 - part 2.pdfShanthalaKV
18CS52 VTU Computer Network & Security
MODULE 1-Part 2
DNS; The Internet's Directory Service: Services Provided by DNS, Overview of How DNS Works, DNS Records and Messages, Peer-to-Peer Applications: P2P File Distribution, Distributed Hash Tables, Socket Programming: creating Network Applications: Socket Programming with UDP, Socket Programming with TCP.
Domain Name System (DNS) - Domain Registration and Website Hosting BasicsAsif Shahzad
I teach Web Technologies course at COMSATS University to undergrad students. These are lectures slides prepared for students. I thought to share it with all. Hope you would like it. It contains good enough details about how DNS, Hosting and Domain Registration works.
Learn about the essentials of the Domain Name System (DNS), including name resolution, different record types, roots, zones, authority and recursion.
See the full webinar and the rest of the series at https://www.thousandeyes.com/resources/intro-to-dns-webinar
Private DNS Infrastructure Support in Hybrid ScenariosDaniel Toomey
A discussion of DNS private resolver architecture, how it is leveraged for private resolution for Azure <-> Azure and Azure <-> On-Prem and other things including private DNS zones and conditional forwarding rules.
As presented to the Brisbane Azure Group by Rachel Calleia (https://www.linkedin.com/in/rachel-calleia-669439144/)
Private DNS Infrastructure Support in Hybrid ScenariosDaniel Toomey
A discussion of DNS private resolver architecture, how it is leveraged for private resolution for Azure <-> Azure and Azure <-> On-Prem and other things including private DNS zones and conditional forwarding rules.
As presented to the Brisbane Azure Group by Rachel Calleia (https://www.linkedin.com/in/rachel-calleia-669439144/)
The Domain Name System (DNS) is a critical part of Internet infrastructure and the largest distributed Internet directory service. DNS translates names to IP addresses, a required process for web navigation, email delivery, and other Internet functions. However, the DNS infrastructure is not secure enough unless the security mechanisms such as Transaction Signatures (TSIG) and DNS Security Extensions (DNSSEC) are implemented. To guarantee the availability and the secure Internet services, it is important for networking professionals to understand DNS concepts, DNS Security, configurations, and operations.
This course will discuss the concept of DNS Operations in detail, mechanisms to authenticate the communication between DNS Servers, mechanisms to establish authenticity, and integrity of DNS data and mechanisms to delegate trust to public keys of third parties. Participant will be involved in Lab exercises and do configurations based on number of scenarios.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
NO1 Uk best vashikaran specialist in delhi vashikaran baba near me online vas...Amil Baba Dawood bangali
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Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Student information management system project report ii.pdfKamal Acharya
Our project explains about the student management. This project mainly explains the various actions related to student details. This project shows some ease in adding, editing and deleting the student details. It also provides a less time consuming process for viewing, adding, editing and deleting the marks of the students.
2. Skills Matrix
Technology Skill
Objective Domain
Objective #
Installing the DNS Server Role
Configure a Domain Name System (DNS) server
2.1
Introducing DNS Zones
Configure DNS zones
2.2
Configuring DNS Resource Records
Configure DNS records
2.3
Configuring Active DirectoryIntegrated Zones
Configure DNS replication
2.4
Introducing the DNS Name Resolution Process
Configure name resolution for client
2.5
3. Domain Name System (DNS)
•Without DNS, your network will most likely not function — clients won’t be able to resolve names to Internet Protocol (IP) addresses.
•In addition, Active Directory clients use DNS to locate domain controllers.
4. HOST file
•Before DNS, name resolution was handled through the use of text files called HOSTS files that were stored locally on each computer.
•The HOSTS file listed each name of the host and its corresponding IP address.
•Whenever a new host was added to the network, an administrator would manually update the HOSTS file with the new host name or IP address information.
5. Questions?
•How do we manage billions of DNS records?
•Can one server handles/stores all DNS records?
•If multiple servers,
–How do the records being stored?
–How administrators can manage these records? Can permission delegations happen?
–How about high availability?
•How a client can resolve name to IP using DNS?
ITMT 1371 – Windows 7 Configuration
5
6. Domain Name System
•DNS because of the following benefits:
–Scalability
–Constancy
–Ease of Use
–Simplicity
7. DNS Namespaces
•A DNS namespace is a hierarchical, tree- structured list of DNS host names or domain name, starting at an unnamed root that is used for all DNS operations.
9. DNS Namespaces
•The DNS namespace has a hierarchical structure and each DNS domain name is unique within a namespace.
•Each domain can have additional child domains.
•At the top of the Internet DNS namespace is the root domain.
–The root domain is represented by “.” (a period).
10. DNS Namespaces
•Under the DNS root domain, the top-level domains, or first-level domains, are organizational types such as .org, .com, and .edu.
–Generic — generic, top-level domain names.
–Country code — Examples of country code domain names are .uk., .jp, and .us.
–Infrastructure domain — .arpa is the Internet’s infrastructure domain name.
12. Traditional Top-Level Domain Names
•com – Commercial.
•.edu – Education.
•.gov – Agencies of U.S. federal government.
•.net – Computers of network providers and ISPs.
•.org – Nongovernmental and nonprofit organizations.
13.
14. DNS Namespaces
•Second-level domains are registered to individuals or organizations.
•Second-level DNS domains can have many subdomains, and any domain can have hosts.
•A host is a specific computer or other network device within a domain.
15. Fully Qualified Domain Name (FQDN)
•DNS uses the fully qualified domain name (FQDN) to map a host name to an IP address.
•An FQDN describes the exact relationship between a host and its DNS domain.
•Example:
–nadc1.redmon.microsoft.com
16. Zones
•DNS hierarchical structure is that workload for name resolution is distributed across many different resources.
•For administrative purposes, DNS domains can be organized into zones.
•A zone is a collection of host name–to–IP address mappings for hosts in a contiguous portion of the DNS namespace.
17. Zones
•Zone data is maintained on a DNS name server and is stored in one of two ways:
–As a text-based zone file containing lists of mappings, called a standard zone or a file-backed zone.
–Within an Active Directory database, called an Active Directory–integrated zone.
18. Standard Primary Zone
•A standard primary zone hosts a read/write copy of the DNS zone in which resource records are created and managed.
•Only one server can host and load the master copy of the zone.
–no additional primary servers for the zone are permitted, and only the server hosting the primary zone is allowed to accept dynamic updates and process zone changes.
19. Standard Secondary Zone
•A copy of the zone file may be stored on one or more servers to balance network load, provide fault tolerance, or avoid forcing queries across a slow, wide area network (WAN) link.
•This standard secondary zone is a read-only copy of the standard primary DNS zone.
•Information from a primary zone is transmitted to a secondary zone by performing a zone transfer, which is done by copying the zone file from the primary server to a secondary server.
20. Zone Transfers
•A zone transfer can be a full zone transfer (called an AXFR), in which the entire contents of the zone is copied from the primary server to the secondary server during each zone transfer.
•An incremental zone transfer (called an IXFR), in which only changed information is transmitted after an initial AXFR, in order to cut down on bandwidth usage between.
21. Forward Lookup Zone
•Most queries sent to a DNS server are forward queries.
–They request an IP address based on a DNS name. Includes Host (A) resource records that translate form host name to IP address.
22. Reverse Lookup Zone
•The Reverse Lookup zone is in-addr.arpa domain.
•Enables a host to determine another host’s name based on its IP address.
–Contains the Pointer (PTR) resource record that translates from IP addresses to host names.
23. Stub Zone
•A stub zone is a copy of a zone that contains only those resource records necessary to identify the authoritative DNS servers for that zone.
•A stub zone is a pointer to the DNS server that is authoritative for that zone, and it is used to maintain or improve DNS resolution efficiency.
•The stub zone contains a subset of zone data consisting of an SOA, an NS, and an A record.
•Like a standard secondary zone, resource records in the stub zone cannot be modified; they must be modified at the primary zone.
24. DNS Server Types
•DNS server types are determined by the type of zone or zones they host and by the functions they perform.
•A DNS server may host either primary or secondary zones or both.
•If the server doesn’t host any zones, it is referred to a caching-only server.
•A server is said to be authoritative for a particular zone if it hosts a primary or secondary zone for a particular DNS domain.
25. Primary Name Server
•Primary name servers have been configured with one or more primary DNS zones.
•When a change is made to the zone data, such as adding resource records to the zone, the changes must be made on the primary server for that zone; these changes will then propagate to secondary name servers.
26. Secondary Name Server
•A secondary name server hosts one or more secondary zone databases.
•Because a zone transfer is used to create a secondary zone, the primary name server and zone already must exist to create a secondary name server.
27. Caching-Only Server
•Caching-only servers do not host any zones and are not authoritative for any domain.
•Caching-only DNS servers start with an empty cache and then add resource record entries as the server fulfills client requests.
•This information is then available from its cache when answering subsequent client queries.
•A caching-only DNS server is valuable at a site when DNS functionality is needed locally but when creating a separate domain or zone is not desirable.
28. AD-Integrated Zones
•Zones are stored in Active Directory.
•No distinction between primary and secondary servers.
•Changes made on one DNS server are replicated to other DNS Server.
29. Installing the DNS Server Role
•Before you can use DNS Server Role, you must install it with Server Manger.
30. Resource Records
•The resource record is the fundamental data storage unit in all DNS servers.
–Start of Authority (SOA)
–Name Server (NS)
–Host (A)
–Host (AAAA)
–Canonical Name (CNAME)
–Mail Exchanger (MX)
–Pointer (PTR)
–Service Record (SRV)
31. Start of Authority (SOA) Resource Records
•Identifies which name server is the authoritative source of information for data within this domain.
–The first record in the zone database file must be an SOA record. In the Windows Server 2008 DNS server, SOA records are created automatically with default values when you create a new zone.
34. Name Server (NS) Resource Records
•Identifies the name server that is the authority for the particular zone or domain; that is, the server that can provide an authoritative name-to-IP address mapping for a zone or domain.
36. A and AAAA Resource Records
•The A resource record is the fundamental data unit of the DNS that is used to translate the host name to the IPv4 address.
•The AAAA resource record is used to translate the host name to the IPv6 address.
•The Pointer (PTR) resource record is the functional opposite of the A record, providing an IP address- to-name mapping, which is found in the reverse lookup zones.
38. Canonical Name (CNAME) Resource Record
•Sometimes called an Alias record, is used to specify an alternative name for the system specified in the Name field.
42. Service Record (SRV)
•Enables clients to locate servers that are providing a particular service.
–Windows Server 2008 Active Directory clients rely on the SRV record to locate the domain controllers they need to validate logon requests.
44. Root Hints
•DNS servers resolve DNS queries using local authoritative or cached data.
•But if the server does not contain the requested data and is not authoritative for the name in a query, it may perform recursive resolution or return a referral to another DNS server depending on whether the client requested recursion.
•The DNS Server service must be configured with root hints to resolve queries for names that it is not authoritative for or for which it contains no delegations.
•Root hints contain the names and IP addresses of the DNS servers authoritative for the root zone. You can use the DNS console to manage the list of root servers, as well as the dnscmd command- line utility.
45. Root Hints
•By default, DNS servers use a root hints file, called cache.dns, on Microsoft DNS servers.
•The cache.dns file is stored in the %systemroot%System32Dns folder on the server computer.
•When the server starts, cache.dns is preloaded into server memory.
•By using root hints to find root servers, a DNS server is able to complete recursive queries.
48. DNS Resolver Cache
•Any Windows computer, key the following at a command prompt:
ipconfig /displaydns:
•To purge the cache, key the following at a command prompt:
ipconfig /flushdns:
49. Forwarders
•A forwarder is a DNS server on a network used to forward DNS queries for external DNS names to DNS servers outside of that network.
•A conditional forwarder forwards queries on the basis of domain name.
55. Dnscmd Command
•You can use the Dnscmd command-line tool to perform most of the tasks that you can do from the DNS console.
•This tool can be used to script batch files, to help automate the management and updates of existing DNS server configurations, or to perform setup and configuration of DNS servers.
•http://technet.microsoft.com/en- us/library/cc756116(v=ws.10).aspx
56. Advanced DNS Server Properties
•Advanced DNS server properties refer to the settings that can be configured in the Advanced tab of the DNS Server Properties dialog box.
•These properties relate to server-specific features, such as disabling recursion, handling resolution of multi-homed hosts, and achieving compatibility with non-Microsoft DNS servers.
58. Summary
•DNS names and the DNS protocol are required for Active Directory domains and for compatibility with the Internet.
•The DNS namespace is hierarchical and based on a unique root that can have any number of subdo-mains.
•An FQDN is the name of a DNS host in this namespace indicating the host’s location relative to the root of the DNS domain tree.
–An example of an FQDN is host1.subdomain.microsoft.com.
59. Summary
•A DNS zone is a contiguous portion of a namespace for which a server is authoritative.
•A server can be authoritative for one or more zones and a zone can contain one or more contiguous domains.
•A DNS server is authoritative for a zone if it hosts the zone, either as a primary or secondary DNS server.
•Each DNS zone contains the resource records it needs to answer queries for its portion of the DNS namespace.
60. Summary
•There are several types of DNS servers: primary, secondary, master name, and caching-only.
61. Summary
•A DNS server that hosts a primary DNS zone is said to act as a primary DNS server.
•Primary DNS servers store original source data for zones.
•With Windows Server 2003, you can implement primary zones in one of two ways: as standard primary zones (zone data is stored in a text file) or as an Active Directory–integrated zone (zone data is stored in the Active Directory database).
62. Summary
•A DNS server that hosts a secondary DNS server is said to act as a secondary DNS server.
•Secondary DNS servers are authoritative backup servers for the primary server.
•The servers from which secondary servers acquire zone information are called masters.
•A caching-only server forwards requests to other DNS servers and hosts no zones, but builds a cache of frequently requested records.
63. Summary
•Recursion is one of the two process types for DNS name resolution.
•A DNS client will request that a DNS server provide a complete answer to a query that does not include pointers to other DNS servers, effectively shifting the workload of resolving the query from the client to the DNS server.
64. Summary
•For the DNS server to perform recursion properly, the server needs to know where to begin searching for names in the DNS namespace.
•This information is provided by the root hints file, cache.dns, which is stored on the server computer.
65. Summary
•A DNS server on a network is designated as a forwarder by having the other DNS servers in the network forward the queries they cannot resolve locally to that DNS server.
•Conditional forwarding enables a DNS server to forward queries to other DNS servers based on the DNS domain names in the queries.