Windows Server 2008 and Windows Server 2008 R2 | Draytek router | stops resolving DNS queries
After a period of time Windows DNS server stops resolving external DNS requests. You can ping/access the sites via the IP address but are unable to have them resolved unless you restarted the DNS Server Service on the Windows Server.
To resolve the issue and continue using root hints, change the MaxCacheTTL registry value to 2 days or greater.
Warning: Serious problems might occur if you modify the registry incorrectly by using Registry Editor or another method. These problems might require you to reinstall the operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.
1. Start Registry Editor (regedit.exe).
2. Locate the following registry key:
4. On the Edit menu, click New, click DWORD (32-bit) Value, and then add the following value:
Data Type: DWORD
Data value: 0x2A300 (172800 seconds in decimal, or 2 days)
5. Click OK.
6. Quit Registry Editor.
7. Restart the DNS Server service.
from: https://support2.microsoft.com/default.aspx?scid=kb;EN-US;968372wrong spellings: dreytec dreytek dreytech