DHCP.DNS & WINS

It is used to auto assigned IP addresses to TCP/IP clients. But we need to give static IP address to DHCP server manually. We can install DHCP only on Win NT server or Win 2k server . There may be any OS on client computer. There must be TCP/IP protocol on both sides. On client computers, in TCP/IP properties, we select ‘ Automatic IP address ' instead of manually.

Installation of DHCP server

1. Select add/remove window components from the add/remove programs of control panel.
2. Check the DHCP from the Detail of Networking Services .
3. When we press OK and then Next, it configure the components. There is no need of Win 2k CD-ROM.
4. We end the wizard by clicking on Finish.

Configuration of DHCP server

1. Open Start à Programs à Administrator tools à DHCP
2. In DHCP dialog box, select system name and select ‘New scope ' from pop-up menu.
3. Click next on welcome screen.
4. In next wizard, we have to provide an identifying scope name . This helps us quickly identifying how the scope is to be used on network.
5. In IP address range dialog box, we define the scope address range by identifying a set of consecutive IP addresses. We enter the start IP address and End IP address . A subnet mask defines how many bits of an IP address to use for the network IDs.
6. In add exclusions wizard, we enter the IP address or a range of address, that are not distributed by the server.
NOTE: - The IP address of Server must be excluded.
7. In Lease duration dialog box, specifies how long a client can use an IP address from this scope. We can give the days, hours or minutes.
NOTE : - By default lease duration in Win NT is 3 days and in Win 2k is 8days .
But in Win NT, we can give unlimited days and in Win 2k, we can give 999 days .
If the server is off, then the network will work up to given limit.
8. In configure DHCP options, it asks for configure DNS sever and WINS settings. We can select ‘Yes' to configure it now or we can select ‘No' to configure later.
9. We complete DHCP by click on Finish.
10. Now we select ‘ Activate ' from the right click of scope. There are further four options in this:
(i) Address Pool : - It shows the range of IP-address range and excluded IP-address.
(ii) Address lease : - It shows the defined IP addresses of client computers on network.
(iii) Reservation : - The IP-address of each computer change after the lease duration. If we want to reserve any address to any computer. Then we reserve it. In this we give reservation name, IP address (reserved) and Mac address of the system.

After this configuration, first client computer request for IP address to DHCP. DHCP server provides a IP address to client in specified range. Then client send a acknowledgement.
NOTE : - In case of Portable computer or Laptop, to get the new address on a new network, we use ipconfig/renew command.

WINS (Window Internet Name Service)

Before 1993, to make the networking, we use a file named LMHOSTS.SAM in folder \winnt\system32\drivers\etc . We make entry of each system on network by edit the file in command mode.

Disadvantages of LMHOSTS.SAM

1. This file has to be edited manually, which becomes a problem in a big network.
2. If a client/server changes the IP address, the entry have to be made in LMHOSTS.SAM file.
WINS resolves NetBIOS name to TCP/IP. WINS increasing network browsing (surfing) and reduced network conjunction. If our LAN has NetBEUI protocol, it can not work over router, so we use ‘ NetBIOS over TCP/IP ' utility to work over router. There is a feature ‘ Dynamic Registration ' in WINS to auto change the IP address.
The IP address of WINS must be static . We can install WINS only on Win NT server or Win 2k server . There may be any OS on client computer. There must be TCP/IP protocol on both sides. On client computers, IP address can be static or manual.
We use two WINS server on a big network.
(i) Primary (ii) Secondary
Features of two WINS are Load balancing & Fault tolerance . Both WINS server replicate with each other.

Multiple servers

In Win NT 4.0 server, we can use 2 WINS servers and we can control about 10,000 clients. But in Win 2k server, we can use 12 WINS servers and can control unlimited clients. First server is called Primary and other servers are called Secondary . There are two ways to resolve ( Only specified computer & To all ).

NODE type

• B-Node (Broadcast) : - It is used for small networks without router.
• P - Node (Point-to-point) : - It is used for small networks, can be used over networks. There is not any fault tolerance i.e. if WINS fails, there is name resolution problem.
• M - Node (Mixed) : - It first used B-Node then P-Node. If B-Node fails, request forward to P-Node.
• H-Node (Hybrid) : - It first used P-Node then B-Node. If P-Node fails, request forward to B-node.
By default Win 2k clients are installed in B-Node and WINS server use H-Node .
Win Proxy agent : - It is third party software which is used for clients, which does not support WINS.

In Win 2k, WINS features

• 12 WINS server
• Load balancing
• Fault tolerance
• Push & Pull replication
• Dynamic registration
• Faster than robust

Installation of WINS

1. Select add/remove window components from the add/remove programs of control panel.
2. Check the WINS from the Detail of Networking Services .
3. When we press OK and then Next, it configure the components. Enter the CD-ROM of Win 2k, when prompted.
4. We end the wizard or completing the installation by clicking on Finish.

To create the database

1. Select the LAN connection from the properties of ‘My network places'.
2. Select the TCP/IP protocol from the properties of ‘LAN connection'.
3. Select Advanced from the properties of TCP/IP.
4. Tab to WINS and add the IP-address of WINS server.
5. If we use LMHOSTS, then we ‘ enable LMHOSTS lookup ' option and import LMHOSTS file.
6. If DHCP is installed then check the option ‘ Use NetBIOS setting from the DHCP server '. Now we need not to confirm the IP-address of WINS server on clients.

Configure WINS server

1. Open Start à Programs à Administrator tools à WINS
2. Select ‘ Active Registration ' from the right click of the server.
3. After activation, right click the server and select find by owner .
4. It displays the list of clients on which we make entry of server.

DNS (Domain Name Service/System)

First internet is used by US army, which is called ARPANET. It has maximum 100 clients. It is used only on CUI. There is a HOST file used to internet. DNS introduced in 1984. It is based on Hierarchical structure, which is introduced in MS-DOS 2.0.

Hierarchical structure
DNS resolves host name to IP address

Advantages of DNS

• We need not to remember the IP address.
• Through name, there is a self advertisement.

Features of DNS

It is fully integrated with Active Directory service.
In a pure Win 2k network, we did not require WINS. DNS will solve the purpose of WINS.
Faster for communication.
More than one DNS solve the purpose of Load balancing & Fault tolerance .
DDNS (Dynamic Domain Name System)
DHCP and DNS integrated.

Installation of DNS server

Before installation check HUB is ON in case of 100 Mbps LAN card, it shows on taskbar. In case of 10 Mbps, no need that HUB is ON.
Select add/remove window components from the add/remove programs of control panel.
Check the DNS from the Detail of Networking Services .
When we press OK and then Next, it configure the components. Enter the CD-ROM of Win 2k, when prompted.
We end the wizard or completing the installation by clicking on Finish.

Configuration of DNS server

1. Open Start à Programs à Administrator tools à DNS
2. Now select computer name and then select New zone from the pop-up menu.
3. Click Next on Welcome screen.
4. In Zone type, select Standard primary . It stores a master copy of new zone in a text file. Standard secondary creates a copy of the existing zone.
5. In this wizard, it asks for forward or reverse lookup zone. A Forward lookup zone is a name-to-address database that helps computers translate DNS names into IP addresses and provides information about available services. A Reverse lookup zone is an address-to-name database that helps computers translate IP addresses into DNS names.
6. Enter the zone name. If we are going to install ADS then we need to add extension of 3 characters with the zone name.
7. Then the zone file name wizard will open. In this we select create a new or use exiting file. The file must be stored in %systemroot%\system32\dns folder with .dns extension.
8. In this step, it shows the description and we complete the configuring by clicking on Finish.
9. Now select the Zone in left side, then in right side select New Host from the right click menu.
10. Enter the name and IP address of computer and click on Add Host .
11. In case of reverse backup zone, we will enter the IP address of network not computer, at place of name. This file is created with name of opposite IP address with extension in-addr.arpa.dns .

To apply DNS

1. Open the properties of ‘My computer'.
2. Tab to Network identification and select the network ID.
3. Click on the DNS, and enter the DNS name.
4. Open More and enter the ‘Primary DNS suffix for this computer'.