Thread: DNS in Windows 2003

Protocol who defined the order of the exchange of information on the Internet, including those described in the system and addressing computers united in this network. Under this system, each computer prisvaivalsya unique four-byte address, which became known as an IP address. Standard new protocol and, consequently, adresovaniya system were adopted in 1982.

But man is much easier to remember some word than four bessoderzhatelnyh number for him. Because of that, immediately after the start of the new network for users began to appear lists, which kept not only addresses, but names and their corresponding nodes.

These data are usually stored in a file named hosts, allowed to identify the host name instantly obtain its IP address. Later in the proofing process of making these files has been improved - hosts the latest version of the file can be downloaded from multiple servers with pre-defined addresses.

With an increasing number of computers in a network manually adjust these files became impossible. There is a need for a global database of names, allowing for an Conversions names to IP addresses without storage at the list of every computer. This base has become a DNS (Domain Name System) - a system for naming domains, which began its work in 1987.

Structure of DNS

On the Internet, there are a lot of DNS servers, offering customers the necessary information on the names of nodes. DNS is the most important quality of their work order, allowing DNS services synchronously update their base. Adding a new address on the web is being held for a few hours.

Zone, domains and subdomains

With an increasing number of domain names work was divided between servers on the principle of unity of command. The idea is simple. If the organization holds its own domain name (eg microsoft.com or white-house, gov), the naming inside your domain, it produces its own. The only difficulty with such work - providing parent servers these rights subordinate servers.

Zone - a container that combines multiple domains in with the overall structure permits the administration, that is, zones are containers for domains and hosts. Zones can be invested in one another. The difference between the zones and domains that domain may belong to multiple zones containing various its subdomains. This makes it possible to delegate authority to manage groups of subdomains and subdomains.

DNS integration in the Active Directory

The company recommends the use of Microsoft DNS servers in corporate networks for the organization of the computers in the composition of the domain. The fact is that technology DNS more versatile and efficient than older systems used at WINS and NetBIOS. Customers only send queries and receive answers server without recourse to any other network nodes.

In terms of productivity best integrate DNS in the Active Directory that is possible on the Microsoft server operating system since Windows 2000 Server. Combining the roles of the DNS server and domain controller simplifies network administration, particularly if the size of its rather high.

What we should build a DNS

DNS implemented according to a common standard, the foundations of which are described in RFC 1035 and 1011.1034. In Windows Server 2003 and the deployment of the DNS management made easier than in previous versions of operating systems, thanks to master server setup roles. In Windows Server 2003 and added new features Active Directory management, which can be integrated with DNS together,

Configuring DNS

After restarting the system in the window "Manage Your Server" (server management) and the "Administration panel will include new elements" - a reference to Active Directory Management Console (three icons), and DNS (an icon). That leaves more for the DNS management console server.

The tree contains a list of DNS servers ONS-ditch, in our case, the list would consist of one item - the name of our server. Disclosing it, we see three folders - "Forward Lookup Zones" (direct viewing zone), "Reverse Lookup Zones" (reverse zone, empty folder) and the "Event Viewer".

Adding new host will occur automatically. All Windows operating systems, starting with Windows 2000 Professional, supports correct updating DNS server in the local network. New items to the list of host names to the DNS server and can be added via "Computer Browser". Manual is the addition of new domains and hosts, as well as the removal of existing menus comes from the "Action" from the context menu or right button mouse.

When you add to the domain computer with the operating system Windows 2000 Professional or Windows XP Professional, the system automatically sends a request DNS server, and that in turn will add a new IP address to the list.

In the network of computers with fixed IP addresses, the DNS is simple. But what happens when your network IP address must be distributed dynamically? Here we are faced with some difficulties, as in this case, the DNS server must constantly update their database, based on data obtained from a DHCP server.

The IP address of the DNS server itself can be dynamic. In this case, for every new computer that provides server functions, configuring network settings when connecting will take place through the DHCP server. Also, not necessarily to DHCP and DNS servers are physically located on a single computer. They will work correctly, even when running on different machines.

DNS server can produce a list of cleaning, removing from it information about those hosts who have been removed from the network. To set clean-up list of hosts, click on "Aging" ( "Cleaning") for the "General" tab in the properties of the zone - by default "overdue" removal of names off (you need to leave the tick). In addition, there is the option to automatically update the states ( "Dynamic Updates") - by default it is set in the "Secure Only" and permit renewal base only on the basis of requests from safe sources.



Connecting to the Internet

U Starter system administrators a lot of problems for incorrect settings of DMS, including the settings on users' computers. First, because everything depends, static or dynamic IP addresses used on your network. In the event that uses a static address, please be sure that each machine properly established its IP address, subnet mask and selectable default DNS server. If computers get their IP addresses dynamically through a DHCP server, the server must also indicate the address and the DNS server. Note that for the correct functioning of clients in the DHCP server should be the only subnet.

Another challenge occurred before administrators - is to configure access to the Internet through a local network. Access can be arranged in different ways, and if all clients are connected through a proxy server, configure DNS to work on the Internet was not necessary. The other case, if you use I-R masquerading using NAT. In this case, the client computers on your network should be able to receive replies from the DNS servers on the Internet to connect to the web servers on their IP addresses.

Realize it's simple. You need to setup forwarding requests from your DNS server in the server Internet service provider called FORWARDING FLEET (). The best way to organize this in two stages. First, your DNS server sends a request to the router, but that already sends its ISP.

You can do one step, because if NAT router provides service to access the Internet, the DNS server itself can apply directly to the ISP. However, this method is less illiterate. For example, if you change provider, you will have to edit the settings already on multiple computers. In addition, connecting to the Internet through NAT is less safe than redirect queries by proxy. Also, for security reasons, is not advisable to combine the role of the DNS server and router on a single computer, especially if it is the same domain controller in your network.

Configuring forwarding happens in the properties of the DNS server management consoles. Push the right button on the server icon, then "Properties -> Forwarders", and point out where the parent domain name or DNS servers list, which will turn our server. On the "Root Hints" lists the addresses of the DNS server of the network (not necessarily superior). List "Root Hints" can be filled automatically with the help of the wizard Configure DNS Server from the menu "Action".

Error is the creation of the zone with the name ".". In this case, our DNS server begins to take root itself, that is the top of the global DNS tree. Of course, any parent sending servers will not work. In establishing the zone, whose name coincides with a part of the already existing zones after a period (for example, we have trading.office zone, but we create a zone of office), all belonging to the zone and domains are embedded in it.

If your server's properties in connection to the local network as a DNS server specified domain controller itself, is not very good. DNS-o Prohibiting questions should never come to the server with its address - any such incident clearly demonstrates the inappropriate settings.

Look at the situation will help "Event Viewer". In the case correctly DNS server should appear in the journal entry on the server launch. Also new listings will appear as you add new names to the hosts either with manual management zones and domains.

In order to detect failure on the part of the client, the easiest way to use the command-line nsLookup that comes with the operating system. After entering nsLookup the command line should appear on your screen name and IP address of your DNS server, and then you will be given an opportunity to test the server by sending queries on behalf of the transformation to an IP address. To see help on the parameters nslookup command, enter the command line nslookup help.