A. The DNS server can check the IP address of a client that's requesting name resolution and sort the results it returns to the client according to the proximity of the host address to the querying IP address. To enable or disable this functionality, perform the following steps on the DNS server:
- Start a registry editor (e.g., regedit.exe).
- Navigate to the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\DNS\Parameters\ registry subkey.
- Double-click LocalNetPriority, or create this value of type DWORD if it doesn't exist.
- Set the value to 1 to enable subnet prioritization or 0 to disable subnet prioritization, then click OK.
- Restart the server for the change to take effect.
Under Windows 2000 and later, you can also use the DNS Management Console to set this functionality. To use this tool to change the setting, go to Start, Programs, Administrative Tools, then click DNS Management Console; right-click the server and select Properties; select the Advanced tab; then clear or select the "Enable Netmask Ordering" check box. You can also control the round-robin functionality by opening the DNS Management Console Advanced tab and clearing or selecting "Enable round robin". The following list describes the expected functionality, depending on the values you set:
- Subnet prioritization disabled, round robin disabled--The DNS server returns records in the order they were added to the database.
- Subnet prioritization enabled, round robin disabled--The DNS server returns records in the order of the local subnet priority.
- Subnet prioritization disabled, round robin enabled--The DNS server returns records in rotation according to the order they were added to the database.
- Subnet prioritization enabled, round robin enabled--The DNS server returns records in rotation according to the local net priority.