DNS resolution on Windows 7
I have Windows 7 and MacOS on Macbook Pro with cable internet connection in hotel. When I am using MacOS, internet connection is just fine. When I am using Windows 7, there is no internet connection. After digging a bit found that DNS resolution is causing the problem, simply names are not resolved. I installed Wireshark and strangely I found in the capture the response to DNS resolution request with resolved IP, but somehow they are not reaching Windows 7 core. Not sure if it's related or not, but after each response I see single STP packet.
The network is using DHCP to setup interface and in both OS's interfaces are setting up identically. I can ping DNS servers, default GW from Windows 7
Update:
nslookup
C:\>nslookup
DNS request timed out.
timeout was 2 seconds.
Default Server: UnKnown
Address: 80.58.61.250
> Yahoo.com
Server: UnKnown
Address: 80.58.61.250
DNS request timed out.
timeout was 2 seconds.
DNS request timed out.
timeout was 2 seconds.
DNS request timed out.
timeout was 2 seconds.
DNS request timed out.
timeout was 2 seconds.
*** Request to UnKnown timed-ou
ipconfig
Windows IP Configuration
Host Name . . . . . . . . . . . . : Mac-Windows 7
Primary DNS Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No
Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Broadcom NetXtreme GBabit Ethernet
Physical Address. . . . . . . . . : C4-2C-03-3B-30-8E
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IPv4 Address. . . . . . . . . . . : 172.31.17.14(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Lease Obtained. . . . . . . . . . : Thursday, December 16, 2010 6:57:58 AM
Lease Expires . . . . . . . . . . : Friday, December 17, 2010 7:01:16 AM
Default Gateway . . . . . . . . . : 172.31.17.254
DHCP Server . . . . . . . . . . . : 172.31.17.254
DNS Servers . . . . . . . . . . . : 80.58.61.250
80.58.61.254
NetBIOS over Tcpip. . . . . . . . : Enabled
Tunnel adapter iSATAp.{5E50E7E1-3532-4D59-97F3-437CB9ABD85B}:
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 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 . . . . : Yes
trace route (result is same for macos as well)
C:\>tracert 8.8.8.8
Tracing route to 8.8.8.8 over a maximum of 30 hops
1 <1 Microsoft <1 Microsoft <1 Microsoft 172.31.17.254
2 * * * Request timed out.
3 * * * Request timed out.
4 * * * Request timed out.
5 * * * Request timed out.
6 * * * Request timed out.
7 * * * Request timed out.
8 * * * Request timed out.
9 * * * Request timed out.
10 * * * Request timed out.
11 * * * Request timed out.
12 111 Microsoft 109 Microsoft 109 Microsoft 8.8.8.8
Trace complete.
netstat
C:\>netstat
Active Connections
Proto Local Address Foreign Address State
TCP 127.0.0.1:5357 Mac-Windows 7:49165 TIME_WAIT
TCP 127.0.0.1:5939 Mac-Windows 7:49164 ESTABLISHED
TCP 127.0.0.1:49157 Mac-Windows 7:49158 ESTABLISHED
TCP 127.0.0.1:49158 Mac-Windows 7:49157 ESTABLISHED
TCP 127.0.0.1:49160 Mac-Windows 7:49161 ESTABLISHED
TCP 127.0.0.1:49161 Mac-Windows 7:49160 ESTABLISHED
TCP 127.0.0.1:49162 Mac-Windows 7:49163 ESTABLISHED
TCP 127.0.0.1:49163 Mac-Windows 7:49162 ESTABLISHED
TCP 127.0.0.1:49164 Mac-Windows 7:5939 ESTABLISHED
This was the reason for DNS not working with DHCP on Windows 7 in my case:
After 2 days of struggling, I suddenly noticed that when I rebooted the router (after modifiyng some basic parameter) its date was probably reset to its BIRTHDATE (2005), so the lease it was giving was in the PAST and probably Windows 7 relies on the date given by the DHCP instead of its own...
The result is that the lease is already over.
Then 2 odd things happen, you can check them with ipconfig /allcompartments /all
on Windows 7, for some reason:
- Windows 7 doesn't understand the lease time: it declares more than 136 years instead of 120 minutes!
- If the lease is ALREADY OVER: Windows 7 ignores the DNS given!
To summarize the SOLUTION in my case was:
- Setup the correct time on the DHCP server.
- Run
ipconfig /release
- Run
ipconfig /renew
DHCP with DNS shoud be UP and WORKING!
So ALWAYS check the DHCP server date...