Using WINS Lookup in DNS Zones
Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2
The DNS Server service provides the ability to use Windows Internet Name Service (WINS) servers to look up names that are not found in the Domain Name System (DNS) domain namespace by checking the network basic input/output system (NetBIOS) namespace that is managed by WINS.
For WINS lookup integration, two special resource record types — the WINS and WINS-R resource records — are enabled and added to a zone. When the WINS resource record is used, DNS queries that fail to find a matched host address (A) resource record in the zone are forwarded to WINS servers that are configured in the WINS resource record. For reverse lookup zones, the WINS-R resource record can be enabled and used to provide a similar benefit for further resolving a reverse query that is not answerable in the reverse in-addr.arpa domain.
For example, you can use WINS lookup when you are using a mixed-mode client environment consisting of UNIX clients that use only DNS name resolution and earlier-version Microsoft clients that require NetBIOS naming. In these environments, WINS lookup provides a method for permitting UNIX DNS clients to locate your WINS clients by extending DNS host name resolution into the WINS-managed NetBIOS namespace.
The WINS lookup integration feature is supported only by Windows DNS servers. If you use a mixture of Windows and other DNS servers to host a zone, you should select the Do not replicate this record check box option for any primary zones when you use the WINS lookup record. This prevents the WINS lookup record from being included in zone transfers to other DNS servers that do not support or recognize this record. If you do not enable the WINS lookup record to be used only on the local server, it can cause data errors or failed zone transfers at servers running other DNS server implementations that replicate the zone:
How the caching Time to Live (TTL) and lookup time-out values are configured for use with the WINS and WINS-R records
The format of the WINS and WINS-R resource records as they are used in zone files that are created by the DNS Server service
WINS Lookup Interoperability
Typically, WINS lookup provides the best and most predictable results if only Windows DNS servers are used, and it is only available directly for use at Windows DNS servers. There are ways, however, that you can use and benefit from WINS lookup as an interoperable solution when other DNS servers are deployed.
For example, consider adding a Windows DNS server that hosts a new WINS lookup-enabled zone. When you create and name the zone, use a subdomain that is added to your existing DNS namespace that is used just for WINS-specific referrals that are added to your DNS domain namespace.
For instance, in sales.wingtiptoys.com, call the zone wins.sales.wingtiptoys.com when you create it. You can then use this new WINS referral zone as the root zone for any of your WINS-aware computers that have names that are not found in your other traditional DNS zones.
To use the WINS referral zone, you must specify its domain name (wins.sales.wingtiptoys.com) in a DNS suffix search list for your clients. The suffix list is configurable as part of the TCP/IP properties for a client connection, and it can be updated either manually, by using Dynamic Host Configuration Protocol (DHCP) or by using Group Policy. As long as the name of the WINS referral zone is included in the domain suffix list, any DNS names that are not resolved in traditional zones can be resolved by using the WINS referral subdomain.
Under normal conditions, this should result in recursion from your other DNS servers to the Windows DNS servers that host the WINS-enabled zone. If the queried host names match NetBIOS computer names that are found in the WINS database, the names are resolved to the Internet Protocol (IP) addresses that are mapped in WINS data there.
In our example, the WINS-enabled zone is used only for WINS lookup; therefore, no additional resource records need to be added to it. In general, WINS records can be added to any forward lookup zone.
By using a specific subdomain just for WINS lookup and specifying a static DNS suffix list to be used in resolving and searching for names, you can prevent unusual situations in which DNS queries for different fully qualified domain names (FQDNs) resolve to the same WINS client name and IP address. This might easily occur if you add and configure many zones at each level of your namespace and enable each of them to use WINS lookup integration.
For example, suppose you have two zones, both configured to use WINS lookup. The zones are rooted and originate at the following DNS domain names:
sales1.wingtiptoys.com.
sales2.wingtiptoys.com.
With this configuration, a WINS client named HOST-A can be unintentionally resolved by using either of the following FQDNs:
host-a.sales1.wingtiptoys.com.
host-a.sales2.wingtiptoys.com.
Advanced Parameters for WINS Lookups
The two following advanced timing parameters are used with the WINS and WINS-R records:
The Cache timeout value, which indicates to a DNS server how long it should cache any of the information that is returned in a WINS lookup. By default, this value is set to 15 minutes.
The Lookup timeout value, which specifies how long to wait before timing out and expiring a WINS lookup that is performed by the DNS Server service. By default, this value is set to two seconds.
You can configure these parameters by using the Advanced button in the zone properties dialog box when you configure the zone. This button appears on either the WINS or WINS-R tab, depending on whether the zone that you are configuring is being used for forward lookup or reverse lookup.
If you are using either the WINS or WINS-R resource record, be aware that the minimum TTL that is set in the start-of-authority (SOA) record for the zone is not the default TTL that is used with these records. Instead, when either an IP address or a host name is resolved with WINS lookup, the information is cached on the DNS server for the amount of time that is configured for the WINS cache time-out value. If this address is then ever forwarded to another DNS server, the WINS cache time-out value TTL is what is sent. If your WINS data rarely changes, you can increase the default TTL of 15 minutes.
Notes
If you have a zone that is configured for WINS lookup, all DNS servers that are authoritative for that zone need to be capable of WINS lookup or you will have intermittent behavior.
Because you can specify that the WINS and WINS-R resource records not be replicated to other DNS servers, you can selectively enable and configure WINS lookup at each of your secondary servers for zones where this feature is used. This is not a standard practice for other types of resource records, which are only to be configured at the primary server for the zone.
For more information about planning DNS zones, see Deploying Domain Name System (DNS) on the Microsoft Web site (https://go.microsoft.com/fwlink/?LinkId=45677).
Task requirements
To begin this task, perform the following requirements:
- Install Dnscmd.
To complete this task, perform the following procedures: