Replacing a WINS Static 1c with a Dynamic Entry with Windows NT 4.0 SP4

ID: Q199159

The information in this article applies to:

SUMMARY

Microsoft WINS stores a list of domain controller IP addresses for a specified domain in a special group record with a [1ch] suffix as its sixteenth character. As this list is replicated between WINS servers, it may accumulate obsolete addresses that are difficult to purge, especially on a large network of WINS servers. Windows NT 4.0 Service Pack 4 (SP4) provides a new feature that allows [1ch] entries to be purged and renewed.


MORE INFORMATION

The ability to purge [1ch] records is a product of an enhancement to Windows NT 4.0 Service Pack 4 (SP4) designed to help removed unwanted static [1ch] entries. Prior to Windows NT 4.0 SP4, a static special group WINS record, of which the [1ch] for a domain is an example, would not be overwritten by a dynamic entry, even with the Wins Migrate on/off feature enabled.

For additional information, please see the following article(s) in the Microsoft Knowledge Base:

Q167806 Explanation of Advanced Options in WINS Manager
This behavior was designed assuming administratively entered entries would always need to take precedence with 1c group lists. To provide an exception when an administrator finds it necessary to replace a static [1ch] entry with a dynamic [1ch] entry, static entries are now overwritten by dynamic entries if the dynamic entry was registered with the same server as the static entry. For this feature to work, all WINS servers in a replication network must have Windows NT 4.0 SP4 or later installed.

Using this feature, it is possible to replicate a static [1ch] entry for a domain name, and then replace it with a dynamic entry on the same WINS server. When the static entry is replicated, it will overwrite any dynamic entries, which will eliminate any obsolete IP addresses that are part of any [1ch] list. When the static entry is then deleted and a dynamic entry is registered on the same server, the dynamic entry will then replace the static entries on other servers. As other domain controllers are added or renew their addresses, they will then be added to the domain [1ch] list.

Again, for this technique to be successful all WINS replication partners involved must have Windows NT 4.0 SP4 or later. If a computer is running Windows NT 4 Service Pack 3 or earlier, it will never overwrite its static [1ch] entry with a dynamic entry from any server. The static entry will need to be removed with the Winscl utility, available in the Windows NT 4.0 resource kit.


REFERENCES

For additional information, please see the following article(s) in the Microsoft Knowledge Base:

Q163409 NetBIOS Suffixes (16th Character of the NetBIOS Name)
Q167365 The Order That WINS Returns 1Ch Entries
Q171794 Migrate On/Off Does Not Allow Static Mappings to Be Overwritten
Q184693 DNS/DHCP/WINS Release Notes for Windows NT 4.0 SP4 Update 


Keywords          : 
Version           : winnt:4.0,4.0 SP4
Platform          : winnt 
Issue type        : kbinfo

Last Reviewed: February 26, 1999