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3. Set a list of DNS servers for the client to use when resolving DNS names. This list includes a preferred DNS server and can also include alternate DNS servers to use if the preferred server is unavailable.

2. Set Primary DNS Suffix in Windows 2000

3. Set Primary DNS Suffix in Windows XP / 2003

4. Set Primary DNS Suffix in Windows VISTA / 2008 / 7

1. Set the DNS suffix search list or search method to be used by the client when it performs DNS query searches for short, unqualified domain names.

2. Set a connection-specific DNS suffix for each particular adapter on a DNS client computer. For example, if the host named Behzad.CyberTech.com is connected to two subnets through different network adapters, the computer can be seen on one subnet as Behzad.Subnet1.Mehrpouyan.com and on another as Behzad.subnet2.Mehrpouyan.com.

3. Modify dynamic DNS update behavior.

What is connection-specific DNS suffix ?

1. The name hosta.public.example.microsoft.com provides access using LAN connection 1 over Subnet 1, a lower speed (10-Mb) Ethernet LAN, for normal access to users who have typical file and print service needs. 2. The name host-a.backup.example.microsoft.com provides access using LAN connection 2 over Subnet 2, a higher speed (100-Mb) Ethernet LAN, for reserved access by server applications and administrators who have special needs, such as troubleshooting server networking problems, performing network-based backup, or replicating zone data between servers. 3. The computer can also be accessed in a manner that does not specify a particular LAN connection. To connect to the computer through either LAN connection, clients specify the computer’s full computer name, host-a.example.microsoft.com.

3. Configure DNS Suffixes on Windows 2000 / XP / 2003

4. Configure DNS Suffixes on Windows Vista / 2008 / 7

When resolving names, the DNS Client service queries the DNS servers in the following order: 1. The DNS Client service sends the query to the first server on the preferred adapter’s list of DNS servers and waits 1 second for a response. 2. If the DNS Client service does not receive a response from the first server within 1 second, it sends the query to the first DNS servers on all adapters that are still under consideration and waits 2 seconds for a response. 3. If the DNS Client service does not receive a response from any server within 2 seconds, the resolver sends the query to all DNS servers on all adapters that are still under consideration and waits another 2 seconds for a response. 4. If the DNS Client service still does not receive a response from any server, it sends the query to all DNS servers on all adapters that are still under consideration and waits 4 seconds for a response. 5. If it still does not receive a response from any server, the resolver sends the query to all DNS servers on all adapters that are still under consideration and waits 8 seconds for a response.

DNS Suffix Search Lists 1. Default DNS Suffix Searches 2. Custom DNS Suffix Search Lists

By default, the DNS Client service first attaches the primary domain suffix of the local computer to the unqualified name. If the query fails to resolve this name, the DNS Client service then adds any connection-specific suffix that you have assigned to a network adapter. Finally, if these queries are also unsuccessful, the DNS Client service adds the parent suffix of the primary DNS suffix.

suppose the full computer name of a multihomed computer is computer1.domain1.microsoft.com. The network adapters on Computer1 have been assigned the connection-specific suffixes subnet1.domain1.microsoft.com and subnet2.domain1.microsoft.com, respectively. If on this same computer you type c omputer2 into the Address text box in Internet Explorer and then press Enter, the local DNS Client service first tries to resolve the name Computer2 by performing a query for the name computer2.domain1.microsoft.com. If this query is unsuccessful, the DNS Client service queries for the names computer2.subnet1.domain1.microsoft.com and computer2.subnet2.domain1.microsoft.com. If this query does not succeed in resolving the name, the DNS Client service queries for the name computer2.microsoft.com.

You can customize suffix searches by creating a DNS suffix search list in the Advanced TCP/IP Settings dialog box

The Append These DNS Suffixes option lets you specify a list of DNS suffixes to add to unqualified names. If you enter a DNS suffix search list, the DNS Client service adds those DNS suffixes in order and does not try any other domain names. For example, if the suffixes appearing in the search list in Figure 4-15 are configured and you submit the unqualified, single-label query “coffee,” the DNS Client service first queries for coffee.lucernepublishing.com and then for coffee.eu.lucernepublishing.com.

1. To configure an additional DNS server IP address, click the topmost Add button and specify a DNS server IP address. 2. To configure the client to resolve an unqualified name by adding the primary DNS suffix and the DNS suffix of each connection (if configured), select Append Primary And Connection Specific DNS Suffixes. If you also want to search the parent suffixes of the primary DNS suffix up to the second-level domain, select the Append Parent Suffixes Of The Primary DNS Suffix check box.

3. To configure the client to resolve an unqualified name by adding the suffixes from a list of configured suffixes, select Append These DNS Suffixes, and then click Add to add suffixes to the list. 4. To configure a connection-specific DNS suffix, type the DNS suffix in the DNS Suffix For This Connection text box.

5. To configure the client to register the connection’s IP address with the local computer’s full computer name in DNS, select the Register This Connection’s Addresses In DNS check box. This option is enabled by default. This option requires that the primary DNS suffix of the computer match a domain hosted by the preferred DNS server. 6. To configure the client to register the connection’s IP address with a connection- specific FQDN, select the Use This Connection’s DNS Suffix In DNS Registration check box. This option is disabled by default.

* : To completely disable DNS dynamic updates for all names on the computer, clear the Register This Connection’s Addresses In DNS check box for all connections in Network Connections.

References : 1. MS Press, , Windows Server 2003 Network Infrastructure 2. OReilly, DNS & BIND, 5 th Edition 3. Network +, DNS Video Clip 4. Willey, , Windows Server 2008 Network Infrastructure 5. MS Press, Security Resource Kit 6.