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Server location move. DC DNS no longer working
Posted on 2012-12-28
I have a tough issue. I have a existing DC that is part of a WAN, and was moved to a new office. It can no longer see the internet. The firewall (Cisco ASA-5505) was changed to use the new internet provider IP, but the server (DC) can't see past the firewall. DNS was configured on this DC years ago and has been working as it should. I have not reconfigured the Site to Site VPN connection to the other offices yet, but this shouldn't be an issue, as they have been offline before.
The internal firewall (gateway) IP address didn't change (10.0.14.4). Server IP is 10.0.14.2. I deleted the forwarders and readded. I added new ones from openDNS. I cleared cache, and restarted the DNS services. Rebooted the server. Changed the ports on the switch.
I can see the internet from the PC's when I manually enter a DNS address outside the network. ie. 4.2.2.2 or 8.8.8.8. When I use the DNS address of the server (DC) it fails. With the internal DNS address in place, I can resolve internal DNS names, but not external ones. I can ping the server using the IP and DNS name from the PC's
When I use the NSlookup I get "timed-out"
Default Server: dc01.domain.local (local DC)
Address: 10.0.14.2 (correct IP)
> google.com
Server: dc01.domain.local
Address: 10.0.14.2
DNS request timed out.
timeout was 2 seconds.
*** Request to dc01.domain.local timed-out
Server is:
Windows 2003 R2 SP2. 4 GIG ram.
I did a route print and the results are below.
IPv4 Route Table
==========================
Interface List
0x1 ..........................
0x10003 ...00 1d 09 ef f3 00 ...... Broadcom NetXtreme Gigabit Ethernet
==========================
==========================
Active Routes:
Network Destination Netmask Gateway Interface Metric
0.0.0.0 0.0.0.0 10.0.14.4 10.0.14.2 10
10.0.14.0 255.255.255.0 10.0.14.2 10.0.14.2 10
10.0.14.2 255.255.255.255 127.0.0.1 127.0.0.1 10
10.255.255.255 255.255.255.255 10.0.14.2 10.0.14.2 10
127.0.0.0 255.0.0.0 127.0.0.1 127.0.0.1 1
224.0.0.0 240.0.0.0 10.0.14.2 10.0.14.2 10
255.255.255.255 255.255.255.255 10.0.14.2 10.0.14.2 1
Default Gateway: 10.0.14.4
==========================
Persistent Routes:
None
Thank you in advance for any help rendered!
2012-12-28---PPDWV-DC01-Forwarde.PNG
The internal firewall (gateway) IP address didn't change (10.0.14.4). Server IP is 10.0.14.2. I deleted the forwarders and readded. I added new ones from openDNS. I cleared cache, and restarted the DNS services. Rebooted the server. Changed the ports on the switch.
I can see the internet from the PC's when I manually enter a DNS address outside the network. ie. 4.2.2.2 or 8.8.8.8. When I use the DNS address of the server (DC) it fails. With the internal DNS address in place, I can resolve internal DNS names, but not external ones. I can ping the server using the IP and DNS name from the PC's
When I use the NSlookup I get "timed-out"
Default Server: dc01.domain.local (local DC)
Address: 10.0.14.2 (correct IP)
> google.com
Server: dc01.domain.local
Address: 10.0.14.2
DNS request timed out.
timeout was 2 seconds.
*** Request to dc01.domain.local timed-out
Server is:
Windows 2003 R2 SP2. 4 GIG ram.
I did a route print and the results are below.
IPv4 Route Table
==========================
Interface List
0x1 ..........................
0x10003 ...00 1d 09 ef f3 00 ...... Broadcom NetXtreme Gigabit Ethernet
==========================
==========================
Active Routes:
Network Destination Netmask Gateway Interface Metric
0.0.0.0 0.0.0.0 10.0.14.4 10.0.14.2 10
10.0.14.0 255.255.255.0 10.0.14.2 10.0.14.2 10
10.0.14.2 255.255.255.255 127.0.0.1 127.0.0.1 10
10.255.255.255 255.255.255.255 10.0.14.2 10.0.14.2 10
127.0.0.0 255.0.0.0 127.0.0.1 127.0.0.1 1
224.0.0.0 240.0.0.0 10.0.14.2 10.0.14.2 10
255.255.255.255 255.255.255.255 10.0.14.2 10.0.14.2 1
Default Gateway: 10.0.14.4
==========================
Persistent Routes:
None
Thank you in advance for any help rendered!
2012-12-28---PPDWV-DC01-Forwarde.PNG
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7 Comments
Active 6 days ago
can you ping to gateway ip from server?
Server internet traffic may block at firewal. Isn't it ?
Server internet traffic may block at firewal. Isn't it ?
To narrow down the issue I suggest do a quick test:
1. On your dc, change the DNS direct to the external dns server.
2. Do a DNS query test to external domain (eg: google.com) and see it is able to resolved it.
1. On your dc, change the DNS direct to the external dns server.
2. Do a DNS query test to external domain (eg: google.com) and see it is able to resolved it.
Changed the DNS to 4.2.2.2 and it doesn't resolve it. I also tried using the IP address of a web site and it was not able to connect.
I can connect to the firewall and edit or view the settings from the server.
I can connect to the firewall and edit or view the settings from the server.
If your gateway set correctly and still able to resolve DNS and not able to connect using IP, it is quite clear that something is blocking it. Check the fw rule and routing. Do a tracert and see if it route correctly and stop where.
Pick an IP address on the other side of the router (like 8.8.8.8 or 4.2.2.2) that you are able to successfully ping from a client, and see if you can ping it from the server. Also, use a client to resolve the IP address of a site you can browse to, and see if you can browse to that IP address from the server. These tests will help determine whether all traffic from the server to the outside is being blocked somewhere, or if only DNS traffic is affected.
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