Single Vista machine connected to DSL modem getting conflict with another computer claiming to be ma

  • Thread starter Thread starter Nubie
  • Start date Start date
Open a command prompt and enter "ipconfig /all", without the quotes. What do
you get?

Other points in-line below.

Nubie said:
0016D3A2E7AD is my machines regular (wire) network card. The wireless
card is disabled in device manager (which presumably rules any wireles
connection out). 68.127.186.255 is AT&T's network, which is my ISP (ARIN
lookup below):

AT&T Internet Services SBCIS-SIS80 (NET-68-120-0-0-1)
68.120.0.0 - 68.127.255.255
bras4.pltnca SBC068127176000040211 (NET-68-127-176-0-1)
68.127.176.0 - 68.127.191.255

The constantly repeating reconnection notices at 5 minute intervals, (with
resulting successfully assigned IP addresses), is probably a result of the
fact that I remove the ethernet cable from my network card whenever I step
away from my machine.
Click to expand...

You really shouldn't do that. Only USB is generally safe to hot-plug. Sooner
or later you're luck will run out and one or the other ethernet devices will
fry. That aside, unplugging it doesn't account for those repeating
reconnections. The timing is too consistent, down to the second.
The only other remotely possible connection to my PC would have been
bluetooth, however the wireless card which provides bluetooth connectivity
is always turned off (at the switch).

This leaves 2 questions

1) How could there be a master browser called JAYS showing up on my logs
(given the above).
Click to expand...

You would both have to be peers connected on the same LAN or directly to
each other (same thing). Any PC on a LAN can be a master browser. I have one
XP PC on mine that always insists on taking that status when it joins the
LAN.
and (less importantly)

2) Why is my machine having a conversation with the outside world (my ISP)
about its workgroup. My understanding was that a workgroup would be
something that would be limited to my LAN alone.
Click to expand...

Let's see what ipconfig shows.
 
Windows IP Configuration

Host Name . . . . . . . . . . . . : mypc
Primary Dns Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No
DNS Suffix Search List. . . . . . : domain_not_set.invalid

Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . : domain_not_set.invalid
Description . . . . . . . . . . . : NVIDIA nForce Networking Controller
Physical Address. . . . . . . . . : 00-16-D3-A2-E7-AD
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
Link-local IPv6 Address . . . . . :
ff80::80f6:625f:f376:8301%6(Preferred)
IPv4 Address. . . . . . . . . . . : 68.127.175.71(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Lease Obtained. . . . . . . . . . : Friday, March 14, 2008 12:05:54 PM
Lease Expires . . . . . . . . . . : Friday, March 14, 2008 3:41:18 PM
Default Gateway . . . . . . . . . : 68.127.175.72
DHCP Server . . . . . . . . . . . : 192.168.0.1
DHCPv6 IAID . . . . . . . . . . . : 203332435
DNS Servers . . . . . . . . . . . : 192.168.0.1
192.168.0.1
NetBIOS over Tcpip. . . . . . . . : Enabled

Tunnel adapter Local Area Connection* 6:

Connection-specific DNS Suffix . : domain_not_set.invalid
Description . . . . . . . . . . . : isatap.domain_not_set.invalid
Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes
Link-local IPv6 Address . . . . . :
ff80::200:5fff:68.128.185.71%14(Preferred
)
Default Gateway . . . . . . . . . :
DNS Servers . . . . . . . . . . . : 192.168.0.1
192.168.0.1
NetBIOS over Tcpip. . . . . . . . : Disabled

Tunnel adapter Local Area Connection* 7:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Teredo Tunneling Pseudo-Interface
Physical Address. . . . . . . . . : 02-00-54-55-4E-01
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes
IPv6 Address. . . . . . . . . . . :
2001:0:4337:9f66:18f9:3343:ff80:50f8(Pref
erred)
Link-local IPv6 Address . . . . . :
ff80::38f9:3343:ff80:50f8%12(Preferred)
Default Gateway . . . . . . . . . :
NetBIOS over Tcpip. . . . . . . . : Disabled

Tunnel adapter Local Area Connection* 14:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : 6TO4 Adapter
Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes

Tunnel adapter Local Area Connection* 10:

Connection-specific DNS Suffix . : domain_not_set.invalid
Description . . . . . . . . . . . : Microsoft 6to4 Adapter #2
Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes
Temporary IPv6 Address. . . . . . : 2002:227f:ff27::227f:ff27(Preferred)
Default Gateway . . . . . . . . . : 2002:f058:6301::f058:6301
DNS Servers . . . . . . . . . . . : 192.168.0.1
192.168.0.1
NetBIOS over Tcpip. . . . . . . . : Disabled
 
Looks like a bit of a dog's breakfast. :-)
Questionable entries marked with -******************

You said earlier that the computer was getting a dynamic IP from your ISP
but the way it is configured below I can't see that happening reliably.
You've got two conflicting DHCP services active.
The default Gateway is set to an internet IP but the DHCP server listed is
the modem/router, which presumable can only supply LAN addresses within its
own network subnet (192.168.0.x). Your ISP will have it's own dedicated DHCP
servers which are on internet IPs. That is where the 68.127.175.71 address
came from. Aside from that the modem's internal DHCP server wouldn't know
which internet IPs were available and which ones were already being assigned
to someone else. This could be where your mystery connection is being
created. Also the subnet mask for your internet IP is set for the
192.168.0.x subnet rather than for internet which is not okay.

Your DNS server is set to a local LAN address (192.168.0.1) rather than the
ISP's DNS servers, which is probably okay if the modem/router has the real
DNS server addresses and DNS forwarding is enabled. Otherwise these lines
should be showing two different IPs from your ISP. NetBios is enabled on
your ethernet TCP/IP adapter but without NAT or firewall protection in the
modem/router this is not a good idea over an open internet connection.

It looks like the modem/router's actual LAN IP is 192.168.0.1. That's the
address you should browse to in IE to access the modem's configuration
pages. How you need to configure the computer's network settings depends on
how the modem has been configured but I think at the very least you should
be disabling the modem's onboard DHCP server if your computer's adapter is
intended to get an address automatically from your ISP. Setting the router's
DNS to pass-through mode rather than forwarding isn't absolutely necessary
but it eliminates the extra rerouting step. In the various DNS Suffix lines
I'd expect to see entries referencing your ISP's domain name. I suspect the
tunnel adapters listed below are just redundant.
 
This one looks totally lost. I'd take all your components back to factory
defaults and start from there again. It'll probably come up all by itself,
or with minor tweaks.
 
The modem is set up for DNS forwarding, and the DNS IP's are configured on
the modem. With regards to the NetBios over TCP/IP, I just disabled this
(thanks for the advice).

What is confusing me here is your comments regarding the DHCP server on the
modem. Presumably, any internet IP address the modem gives me has to have
come from the ISP. The ISP assigned the internet IP to the modem, the modem
assigns this to me. (Even if I unplugged my machine from the modem for 30
mins).

How would the above cause the confusion wrt another machine ('JAYS')
appearing to be on my network?
Somehow a NetBIOS message was broadcast, to this other machine on what the
modem/router believed to be my network. How could this have happened?
 
Anything specific?
Just based on my own configs, present and past ,with various hardware and
Windows OS's. Trying to be as generic as possible under the circumstances.
 
Well, I am afraid to say, you can't just do that. Network provider have
and architecture that they follow that dictate how you should set up you
modem and router (if you have one). Some have static IPs (but are fading
out fast). Some want the IP to go to you modem and pass through, others
expect your modem/router DNS to be turned on and a (NAT) translation to
occur and you have your local DNS on. And other things. You can't mix the
settings rules they set up and it's hard to predict what they want unless
it's a known carrier with some of the very common setup we all know by now.
This is probably why JAYS is showing up. So you said you sent a query into
your provider. I'd suggest calling them. Tell them it is an initial setup
and you need directions. BTW your modem is on their approved list. Is it
not.? I am also surprised you can not get to their help/setup page, from
another computer maybe. The setup info has got to be there for you. You
are not alone. Please check with them.
 
Replying inline.

Nubie said:
The modem is set up for DNS forwarding, and the DNS IP's are configured on
the modem. With regards to the NetBios over TCP/IP, I just disabled this
(thanks for the advice).
Click to expand...
What is confusing me here is your comments regarding the DHCP server on
the modem. Presumably, any internet IP address the modem gives me has to
have come from the ISP. The ISP assigned the internet IP to the modem,
the modem assigns this to me. (Even if I unplugged my machine from the
modem for 30 mins).
Click to expand...

I've been having second thoughts about this configuration issue. I tried to
imitate your settings on the PC but couldn't manually change the gateway in
Vista when automatic configuration is enabled. It threw into doubt my
premise that your DSL configuration should be basically similar to mine
despite the different hardware. There are other ways it could be done, with
or without routing. I think at this point it would fruitless to go on
without knowing the details of your ISP's connection specs, the make and
model of your modem and possibly its firmware revision (standard retail
version or custom firmware for the ISP).
How would the above cause the confusion wrt another machine ('JAYS')
appearing to be on my network
Somehow a NetBIOS message was broadcast, to this other machine on what the
modem/router believed to be my network. How could this have happened?
Click to expand...

I'm only speculating. Your system was set with Netbios enabled on the
internet connection, making it accessible from the internet if anyone knew
to find it, or by accident. The speculation is that every so often DHCP
reconfigures the ethernet connection with a LAN address (we saw that in the
logs you posted) while there happened to be a live connection to someone
else who also has Netbios exposed to the internet. The two computers try to
connect to each other on the accidentally "spoofed" Lan connection. Unless
the connection to JAYS keeps reappearing from time to time I'm leaning
towards considering it a fluke occurrence.
 
[snip]

Do you really need to post such large messages?

For those who would fault me for oversnipping - I refer you to this message
for continuity.

Message-ID: <[email protected]>
 
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