Windows 2008 R2, 2 network card (one disabled), sole domain controller Approximately every 35 hours DNS fails. The first sign of it happening is in the event log for Active Directory Web Services. Event ID 1206 "Active Directory Web Services was unable to determine if the computer is a global catalog server" The same event is then reported every 1 minutes after that. Slowly but surely other components start failing (anything that needs to resolve a name - active directory, web access etc) Restarting DNS, ADWS services etc is to no avail. The only thing that is unusual about this server is that one network has 2 IP addresses assigned. When things have gone wrong runing DCDiag gives the following result: "ladap search capability attribute search failed on server BISSVR01, return value = 81 Not sure if ADWS failure is the cause or just a symptom. I am guessing that DNS is to blame, but I can't find anything wrong with the configuration. Following a server restart everything works fine for another 35 hours.... X

Hello, let's start with an unedited ipconfig /all from the DC in question. A DC should NEVER use more then one NIC or multiple ip addresses. And as you state this is the case. This always result in multiple problems within a domain and DNS. More detaila about are in the great arcticle from Ace Fekay: http://msmvps.com/blogs/acefekay/archive/2009/08/17/multihomed-dcs-with-dns-rras-and-or-pppoe-adapters.aspxBest regards Meinolf Weber Disclaimer: This posting is provided "AS IS" with no warranties or guarantees , and confers no rights.

Thanks for the reply. Ok, I can understand multiple IP addresses on the same NIC will cause problems. Why would this only happen 3 months after the server has been running with the same configuration? Is there any rythme or reason as to why it now fails 35 hours after a restart? Is there a process that will run every 35 hours? (Asking the question to learn rather than doubt that its a problem.) Alasdair Windows IP Configuration Host Name . . . . . . . . . . . . : BISSVR01 Primary Dns Suffix . . . . . . . : NOTPUBLICINFO.local Node Type . . . . . . . . . . . . : Hybrid IP Routing Enabled. . . . . . . . : Yes WINS Proxy Enabled. . . . . . . . : No DNS Suffix Search List. . . . . . : NOTPUBLICINFO.local PPP adapter RAS (Dial In) Interface: Connection-specific DNS Suffix . : Description . . . . . . . . . . . : RAS (Dial In) Interface Physical Address. . . . . . . . . : DHCP Enabled. . . . . . . . . . . : No Autoconfiguration Enabled . . . . : Yes IPv4 Address. . . . . . . . . . . : 192.168.200.112(Preferred) Subnet Mask . . . . . . . . . . . : 255.255.255.255 Default Gateway . . . . . . . . . : NetBIOS over Tcpip. . . . . . . . : Enabled Ethernet adapter Local Network: Connection-specific DNS Suffix . : Description . . . . . . . . . . . : Broadcom BCM5709C NetXtreme II GigE (NDIS VBD Client) #2 Physical Address. . . . . . . . . : 00-1A-64-B6-F6-B4 DHCP Enabled. . . . . . . . . . . : No Autoconfiguration Enabled . . . . : Yes IPv4 Address. . . . . . . . . . . : 192.168.200.1(Preferred) Subnet Mask . . . . . . . . . . . : 255.255.255.0 IPv4 Address. . . . . . . . . . . : 192.168.200.2(Preferred) Subnet Mask . . . . . . . . . . . : 255.255.255.0 Default Gateway . . . . . . . . . : 192.168.200.254 DNS Servers . . . . . . . . . . . : 192.168.200.1 192.168.200.2 NetBIOS over Tcpip. . . . . . . . : Enabled Tunnel adapter isatap.{9506D3C0-D5D3-402F-BA2C-668B4A67433E}: Media State . . . . . . . . . . . : Media disconnected Connection-specific DNS Suffix . : Description . . . . . . . . . . . : Microsoft ISATAP Adapter Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0 DHCP Enabled. . . . . . . . . . . : No Autoconfiguration Enabled . . . . : Yes Tunnel adapter isatap.{6E06F030-7526-11D2-BAF4-00600815A4BD}: Media State . . . . . . . . . . . : Media disconnected Connection-specific DNS Suffix . : Description . . . . . . . . . . . : Microsoft ISATAP Adapter #2 Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0 DHCP Enabled. . . . . . . . . . . : No Autoconfiguration Enabled . . . . : Yes Tunnel adapter Teredo Tunneling Pseudo-Interface: Media State . . . . . . . . . . . : Media disconnected Connection-specific DNS Suffix . : Description . . . . . . . . . . . : Teredo Tunneling Pseudo-Interface Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0 DHCP Enabled. . . . . . . . . . . : No Autoconfiguration Enabled . . . . : YesX

Hello, you can be lucky that this only happens after long time, this doesn't belong to a specific interval, maybe it belongs to some router maintenance on your ISP provider, i have no idea. As you have seen in the article from Ace Fekay using RRAS on a DC is a bad option. So reconfigure your network and use a member server for RRAS. If not possible follow the recommendations in the article. Also remove one ip address from the 192.168.x.x addresses. Then cleanup the DNS zones from the removed one, run ipconfig /flushdns and ipconfig /registerdns and restart the netlogon service or reboot.Best regards Meinolf Weber Disclaimer: This posting is provided "AS IS" with no warranties or guarantees , and confers no rights.