MaxCacheTtl

HKLM\SYSTEM\CurrentControlSet\Services\DNS\Parameters

Data type Range Default value
REG_DWORD 0x0 | 0x1 - 0xFFFFFFFF seconds 0x15180 (86,400 seconds = 1 day)

Description

Determines how long a record of a recursive name query can be saved by the DNS server.

If the value of this entry is 0x0, the DNS server does not save any records.

The DNS server saves the records of recursive names queries in a memory cache so that it can respond quickly to new queries for the same name. Records are deleted from the cache periodically to keep the cache content current. The interval during which the record remain in the cache usually is determined by the value of the Time to Live (TTL) field in the record. MaxCacheTtl establishes the maximum time that records can remain in the cache. The DNS server deletes records from the cache when the value of this entry expires, even if the value of the TTL field in the record is greater.

Change method

To change the value of this entry, use Dnscmd.exe, a tool included with the Windows 2000 Support Tools. The change is effective immediately; you do not have to restart the DNS server.

Activation method

DNS reads its registry entries only when it starts. If you change the value of this entry by editing the registry, the changes are not effective until you restart the DNS server.

Note Image Note

This entry does not affect WINS data saved in the DNS memory cache. WINS data is saved until the Cache Timeout Value on the WINS record expires. To view or change the Cache Timeout Value on the WINS record, use the DNS snap-in. Right-click a zone name, click Properties, click the WINS tab, and click the Advanced button.