Please Help! - Strange IP issue with broadband

FrankGrimes

Hi,

I’ve been having a problem with my broadband since last Thursday. I installed WebGuide3 then which is a web based plugin for Windows Media Center but I don’t see how this could have impacted it (I restored to before this point and no joy). Over the weekend my signal was just getting really slow and then wham it would be back up to 300kb downloads and then bam it just stopped working.

Its NTL 3Mbps cable broadband. I have a Linsksy A&G Wireless Router which is connected to the PC and cable modem, (and also some other devices). For the past few days I get no signal whatsoever and I think the problem is on my side as when I run IPconfig my IP address is 198.162.100.10 or something similar. This is the IP address when I have the router connected, but I still get this now even when the router is disconnected and taken out of the loop. My IP address usually looks like 81.xxx.xxx.xxx .

Is this an internal IP address and how do I get back to getting a proper IP when connecting the cable modem directly to the PC? I work 16 hour days at the moment so barely have time to look into this, but would really really appreciate a hand, not least because if I can check mails from US at bedtime it gives me an extra hour in bed in the morning.

As it’s a Media Center PC I am using a 6 to 1 splitter provided by NTL to feed PC with both broadband and PC signals, this was working fine up to this week and even when I take the splitter out of the loop and connect the directly I still get no joy. Any ideas?

ronanp

Your router seems to be set to be a dhcp server. To get rid of the private address (192.168.x.x), type "ipconfig /release" from a command prompt. Then, when connected only to your cable modem, ipconfig /renew should give you a valid IP from your ISP

FrankGrimes

thanks ronan - but I've already tried that and no joy

I unplugged the cable modem and PC. wait 30 seconds. powered on cable modem after connecting directly to PC. wait 30 seconds. powered on PC. did ipconfig /release ipconfig /renew and I get the same 19x.xxx.xxx.xx IP address.

Any other ideas on how I can change it from DHCP (whatever that is!)?
Nice one

irlrobins

is ur pc set to have a static or dynamic ip address?

FrankGrimes

I don't recall actually setting this value (where would I do this?) but the connection has been running fine for the past month since it was setup and NTL use dynamic IP addresses (I've definitely had a few different ones), though this setting may have gotten changed - where should I look?

Thanks.

irlrobins

Start->Settings->Network Connections

Right click on Local Area Connection and choose properties.

Choose TCP/IP Protocol and click on properties.

It should be set to Optain an IP address automatically and Obtain DNS server automatically.

FrankGrimes

thanks, will give that a shot when I get home later and post back with the outcome. fingers crossed

wayne040576

This seems very similar to the problem I have been having since last week with my NTL connection.

I I posted here earlier http://www.boards.ie/vbulletin/showthread.php?t=2054847554

and then saw this thread.
I started having problems with my connection around the same time as you, and I'm also having trouble getting a valid ip address if I retart the modem. Over the weekend I connected one pc directly to the modem and it was taking almost up to an hour (worst occaseion) before ipconfig would get an address. By any chance have you noticed if the Ready light on your modem is blinking for a long time after you restart it? I think it is supposed to go on solid when it syncs with the server, but mine seems to be taking ages to do this. the 192.168.. address you are getting is just directly from the modem itself when it can't forward one from the dhcp server.

Diabolus

I get this problem when i switch from one PC to another.
My solution is simple.

1. Power off Cable Modem
2. Disable LAN Connection
3. Power on Cable Modem
4. Wait for SYNC light to come on
5. Enable the LAN Connection

It would appear that the modem gives the 192.... address to any PC.
Then it assigns the Public IP to the MAC address it has stored.
This seems to clear it.

If not call NTL.
Might be a bogey modem.

wayne040576

Diabolus wrote:

I get this problem when i switch from one PC to another.
My solution is simple.

1. Power off Cable Modem
2. Disable LAN Connection
3. Power on Cable Modem
4. Wait for SYNC light to come on
5. Enable the LAN Connection

It would appear that the modem gives the 192.... address to any PC.
Then it assigns the Public IP to the MAC address it has stored.
This seems to clear it.

If not call NTL.
Might be a bogey modem.

Yeah the modem will only assign an ip address to the mac address of one device at a time. Usually powering down for a while will sort this. But in the last week I've found that it's not working correctly. In my case, I don't think it is the modem, but a fault in the connection itself.

Rodo

Is the ready light on the modem on, or flashing ?
If it's on, you have a connection to the network, if it is constantly flashing, you don't

wayne040576

Rodo wrote:

Is the ready light on the modem on, or flashing ?
If it's on, you have a connection to the network, if it is constantly flashing, you don't

It goes on eventually after at least 20 mins and sometimes up to an hour. It stays on solid then for most of the time but I noticed that when the connection goes bad it flashes off for half a second every now and then. My connection was ok last night give or take so I thought the problem had been sorted. But I checked again this morning before heading to work and it was completely dead.

FrankGrimes

I checked the TCP/IP settings last night and they are both on 'obtain automatically' so thats not it.

Good to hear I'm not the only one having this problem, and I agree that it does sound like a problem on NTLs side.

I will have to double-check tonight but I do seem to recall the Ready light is continually flashing, at least intermittently, whereas I imagine this should be a steady light.

Diablus - do you mean to literally right click the network connection in the Network Connections screen and then click disable and then re-enable when sync light is on? I'll give this a go tonight but I think the flashing Ready (and I think the sync light flashes aswell) light might affect this.

wayne - seems like we have the same problem, and cos its at the same time I doubt its an issue on our sides. I won't be home before 8pm tonight so can't ring NTL. Let me know if you do and if you get it sorted.

Nice one.

wayne040576

FrankGrimes wrote:

I checked the TCP/IP settings last night and they are both on 'obtain automatically' so thats not it.

Good to hear I'm not the only one having this problem, and I agree that it does sound like a problem on NTLs side.

I will have to double-check tonight but I do seem to recall the Ready light is continually flashing, at least intermittently, whereas I imagine this should be a steady light.

Diablus - do you mean to literally right click the network connection in the Network Connections screen and then click disable and then re-enable when sync light is on? I'll give this a go tonight but I think the flashing Ready (and I think the sync light flashes aswell) light might affect this.

wayne - seems like we have the same problem, and cos its at the same time I doubt its an issue on our sides. I won't be home before 8pm tonight so can't ring NTL. Let me know if you do and if you get it sorted.

Nice one.

I actually rang them a few days ago. I have somebody coming out to the house on Saturday but I doubt it will be sorted then.

JanneG

The 192.X.X.X address that you're getting is an address that Windows automatically assigns when it can't reach a DHCP server at all. Normally
does it so that you won't get any error messages popping up.

Check with NTL if there's a static address and subnet mask that you could set on your machine just to verify if you can access anything on their network as you then at least will now if it's your machines TCP/IP stack that might have gone AWOL or if there's an issue with the connection in to your place.

irlrobins

nope, its 169.x.x.x you're thinking of. 192.168.x.x is generally the ip address assigned for use with an internal gateway/router.

JanneG

V. true...

Is there a DHCP service kicked in somewhere on the machine then?

I'm assuming that the machine has been connected directly to the bb modem without the linksys router being involved? And this is when you still get the same address?

wayne040576

JanneG wrote:

V. true...

Is there a DHCP service kicked in somewhere on the machine then?

I'm assuming that the machine has been connected directly to the bb modem without the linksys router being involved? And this is when you still get the same address?

In my case I've actually connect several devices to the modem:
A windows pc
pc running Smoothwall firewall (this is usually connected to it)
ANother linux pc
My linksys wireless router.

In all cases they get the 192.168... address when I first turn the modem on.
I have to make several dhcp requests over the next hour before I finally get a
valid ip.

FrankGrimes

yep, the address i get is 192.168.10.100.

I have removed the router from the loop and now connect the bb modem directly to the pc but am getting the same ip address.

anyway i can re-install the TCP/IP stack to rule it out?

JanneG

Check to see if there's any DHCP services running on your machine just to be sure. If there is no such services then do reinstall the TCP/IP stack.

FrankGrimes

Hey JanneG,

Sometimes I wonder how I managed to get them to give me a computer science degree but networking was, ahem, not my forte and I don't have a clue what DHCP is (or how to detect services running it) or how to reinstall the TCP/IP stack Any pointers for this shamed former student?

Rodo

FrankGrimes wrote:

Hey JanneG,

Sometimes I wonder how I managed to get them to give me a computer science degree but networking was, ahem, not my forte and I don't have a clue what DHCP is (or how to detect services running it) or how to reinstall the TCP/IP stack Any pointers for this shamed former student?

DHCP is a protocol that allows a DHCP server to automatically assign an IP address to a computer.
It's no big deal about it but if you want to see if you actually have DHCP set up, (which should be done automatically) do the following:

1. Open Network Connections
2. Right Click on your ntl broadband connection
3. Now you will see the General tab.
4. Scroll down in the 'this connection uses the following items: to Internet Protocol (TCP/IP), select this option, then click on properties. On the bottom of the new window select Advanced. In the IP addresses section, you should see DHCP enabled.

I reckon Frank, and it's only an opinion that the problem is with the levels coming into your place. I've read that you are working a lot you should phone ntl, even from your workplace, and tell them the problem you are encountering. I know the modem is doing strage things, but they can check your connection with their diagnostic tools.
Explain your situation to them that you are not in the house/apt, but leave the modem, running, off or on depending wheter you are getting a connection or not. Of course.
The intermittent connection you have will show up on their diagnostics
From the diagnostics they can see, how many times your modem has been online/offline since you got the thing. the SNR, etc, etc.
Explain to them that you've bypassed the router, and are using the ethernet lead (I take it thats what you are using, and not the usb lead that came in the box).
When they have checked the diagnostics, then they can determine if it is indeed the network i.e., the levels going and coming from your modem. They will then either issue a service call or not

FrankGrimes

Thanks Rodo.

Will check the DHCP settings tonight (think I recall seeing that this is enabled).

And I'll call NTL tomorrow and see what they can do.

Thanks,
Grimey

FrankGrimes

I left the PC on all day while at work on Friday. Rang NTL that evening from work and they said the last IP address I got was at 10 am that morning. One before that was 4 days previously.

Rang girlfriend to check the connection - and of course it was back working :rolleyes: so we didn't get a chance to diagnose it. Has been ok since, but I'd like to know what the problem was for sure (as it is I think it was NTL's fault but can't blame them without evidence).

I've now got a separate issue with my router but that's for another thread.