Server Behavior

You can configure the server to perform scavenging automatically, using a fixed frequency. In addition, you can manually trigger scavenging on a server to perform immediate scavenging. When scavenging starts, the server attempts to scavenge all primary zones and succeeds if all the following conditions are met:

• The EnableScavenging parameter is set to 1 on the server.

• The EnableScavenging parameter is set to 1 on the zone.

• Dynamic update is enabled on the zone.

• The zone parameter ScavengingServers is not specified or contains the IP address of this server.

• The current time is greater than the value of the zone parameter StartScavenging .

Note

The zone parameter ScavengingServers is configurable only by using Dnscmd.exe. For more information about Dnscmd.exe, see Windows 2000 Support Tools Help.

The server sets StartScavenging whenever any of the following events occur:

• Dynamic update is turned on.

• EnableScavenging is set from 0 to 1 on the zone.

• The zone is loaded.

• The zone is resumed.

StartScavenging is equal to the time that one of the preceding events occur plus the amount of time specified in the refresh interval for the zone. This prevents a problem that can occur if the client is unable to refresh records because the zone isn't available — for example, if the zone is paused or the server is not working. If that happens and the server does not use StartScavenging , the server could scavenge the zone before the client has a chance to update the record.

When the server is ready to scavenge records, it examines all the records in the zone one by one. If the timestamp is not zero and the current time is later than the time specified in the timestamp for the record plus the no-refresh interval plus the refresh interval for the zone, it deletes the record.