ICMP Destination Unreachable, Code:3 SBS 2008
Posted on 2011-10-28
I have a SBS2008 Server (DC), and a Standard Windows Server 2008 (BDC) on my network with a SonicWall TZ210 acting as the gateway to the outside internet. Both DC's are on the same subnet.
I am having problems getting my SBS2008 (Dell PowerEdge T610) to answer DNS requests OUTSIDE our network. The server cannot access anything on the internet UNLESS I put my Backup DC in the NIC's alternate DNS field for the server. If I allow my BDC to act as a secondary DNS on my PDC, I can send/receive email, etc and browse the internet on the PDC. When I remove it, I cannot access the internet on my PDC (SBS).
Interesting note...when I remove the Backup DNS on my PDC, I *can* search google, but when I try to click a search result (a site not in the cache), the connection fails.
On the sonicwall, I went to the log and set my destination IP to the same as my SBS. From the SBS, I tried to ping google.com. I get several logs in the Sonicwall - "ICMP Destination Unreachable, Code:3".
Try the same thing on my BDC, it answers fine, don't get any errors logged in the sonicwall.
I have run the Internet Connection Wizard...it's telling me that it can't get outside my router/firewall. One of the last steps in the wizard is to "test", and it returns that it can't connect to the internet (although I can at that time by going to a web browser).
The ethernet adapter on the Dell SBS is a Broadcom BCM5709C NetXtreme II GigE (NDIS VBD Client). I can nslookup successfully any computer internally on the same subnet as the SBS, but nothing outside.
It appears that this is a problem on my BDC, but I can't figure out how to fix it.