We've deployed our first 2008 R2 server on a client site which has replaced their existing 2003 DC. This server provides DNS resolution services to all client machines on that site for general internet usage.

Since using the 2008 R2 DNS services we have noticed every couple of days the DNS server starts timing out when requests to certain sites are made (google is the only example I can provide at this time although it seems to be larger sites with problems rather than small - CDN compatiblity issue?). When you restart the DNS Server service then resolution returns to normal... just only for a day or so.

Is anybody aware of any significant changes to the DNS server architecture or configuration out of the box in R2 that may explain this intermittent behaviour?

I have already tried the fix listed here to no avail:

http://weblogs.asp.net/owscott/archive/2009/09/15/windows-server-2008-r2-dns-issues.aspx

The following PS command prompt info illustrates the issue:

PS C:\Users\Administrator.UK> nslookup 
Default Server: s8209001.uk.kingdomfaith.com 
Address: 10.1.3.4 > www.google.com 
Server: s8209001.uk.kingdomfaith.com 
Address: 10.1.3.4 Non-authoritative answer: 
Name: www.l.google.com 
Addresses: 66.102.9.99 66.102.9.104 66.102.9.105 66.102.9.103 66.102.9.147 
Aliases: www.google.com > www.google.co.uk 
Server: s8209001.uk.kingdomfaith.com 
Address: 10.1.3.4 * s8209001.uk.kingdomfaith.com can't find www.google.co.uk: Server failed