# Ethernet doesn't have a valid IP configuration



## Tobias Rieper

Hello,

I have a brand new PC workstation.

Everything was fine, until recently, when I turn on my PC, I don't get an immediate internet connection.  This is happening nearly everytime now with some frequency.

I reset the router/modem and everything is fine after that, so all is good.

But it is still frustrating.  I get, *"Ethernet doesn't have a valid IP configuration".*

I googled this and it appears I am certainly not alone.

The following to assist you are screenshots of my 'ipconfig' and 'Network Connection Status'* before* (unsuccessful) and* after* (successful) internet access:






















You will see from the above that there is certainly something different with the data...

I'm sure it is something so simple.
____________________________________________

Incidentally, I did find a nice youtube 'tutorial' in relation to this subject title about manually configurating the settings:

http://www.youtube.com/watch?v=onXsKTAxYtk

I haven't tried this yet and that is probably down to the fact that I can't find my *alternate DNS server* setting (the very last box to fill in - watch the video and you will know what I mean) ???

Many thanks for reading, please help me.


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## Cromewell

From the IP address you are getting it looks like you are behind a router/switch but I'm not sure, the default lease range on the common ones don't normally hand out .254 first. What does your set up look like?

I'm guessing there's a problem with your DHCP server. Your router's config pages should have options for turning it on/off.

If you want to use manual configuration instead, that's fine. You don't have to use your ISPs DNS servers, you can use Google's DNS servers if you'd like https://developers.google.com/speed/public-dns/ Alternatively, OpenDNS has some you could use too. http://www.opendns.com/ (there are others)


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## johnb35

Yeah, looks like a configuration issue.  Check your tcp/IP settings to make sure its set to get IP and DNS automatically.  Also make sure the router is hooked up properly.  Sometimes this will happen when you have the modem hooked to an lan port instead of the wan port.


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## Tobias Rieper

johnb35 said:


> Yeah, looks like a configuration issue.  Check your tcp/IP settings to make sure its set to get IP and DNS automatically.  Also make sure the router is hooked up properly.  Sometimes this will happen when you have the modem hooked to an lan port instead of the wan port.



Hi Jon,

It is set up to automatic, here:






This is where the problem lies I believe.

I think I have to set it up manually, that youtube link explains it and worked for that guy.

You can see from the ipconfig information above that the default gateway is missing when I dont have internet access.  When I have it, it is there, please have a look at the before and after.

Also, the IPv4 addresses are slightly different in the before and after ???

Im a newbie - what do you mean and how do I know if its hooked up to a lan or wan port?


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## Tobias Rieper

Cromewell said:


> From the IP address you are getting it looks like you are behind a router/switch but I'm not sure, the default lease range on the common ones don't normally hand out .254 first. What does your set up look like?
> 
> I'm guessing there's a problem with your DHCP server. Your router's config pages should have options for turning it on/off.
> 
> If you want to use manual configuration instead, that's fine. You don't have to use your ISPs DNS servers, you can use Google's DNS servers if you'd like https://developers.google.com/speed/public-dns/ Alternatively, OpenDNS has some you could use too. http://www.opendns.com/ (there are others)



I have a wired ethernet connection with a modem/router.

When you say, 'what does my set up look like', what do you mean exactly? (I'll show you of course)

FYI, the .254 set up was the one that was working correctly?

What do you mean" I'm guessing there's a problem with your DHCP server. Your router's config pages should have options for turning it on/off."

Please explain?  

Bearing in mind, when I reset my router by pressing the switch and waiting for the blue lights to flush, it works, it is fine.  *It is only when I start my PC up from fresh?*


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## johnb35

Well according to this image.






Your gateway is 192.168.1.254

Your ipv4 address is 192.168.1.64

This is why its not getting a valid IP.  Usually a gateway will have an internal IP of say 192.168.1.1 and any devices attached to it will have an IP of say 192.168.1.101, 192.168.1.102 and so on.  There is something definately wrong with the configuration.  Can you tell me what router and modem you have?  Is it a modem and router all in one or are they separate units?


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## Okedokey

I would just restart all your routers/modems and computers.  It will sort itself out i think.


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## Cromewell

Tobias Rieper said:


> I have a wired ethernet connection with a modem/router.
> 
> When you say, 'what does my set up look like', what do you mean exactly? (I'll show you of course)
> 
> FYI, the .254 set up was the one that was working correctly?
> 
> What do you mean" I'm guessing there's a problem with your DHCP server. Your router's config pages should have options for turning it on/off."
> 
> Please explain?
> 
> Bearing in mind, when I reset my router by pressing the switch and waiting for the blue lights to flush, it works, it is fine.  *It is only when I start my PC up from fresh?*


Sorry, I read your IP screenshot wrong. It kind of sounds like your router needs a restart (as suggested by okeydokey). If there's updated firmware you could try that as well, perhaps it's caused by a bug.


johnb35 said:


> Well according to this image.
> 
> <cut image>
> 
> Your gateway is 192.168.1.254
> 
> Your ipv4 address is 192.168.1.64
> 
> This is why its not getting a valid IP.  Usually a gateway will have an internal IP of say 192.168.1.1 and any devices attached to it will have an IP of say 192.168.1.101, 192.168.1.102 and so on.  There is something definately wrong with the configuration.  Can you tell me what router and modem you have?  Is it a modem and router all in one or are they separate units?


Looks like a gateway of 192.168.1.254 is expected for some routers (most are 192.168.1.1) but Bellsouth hardware in particular seems to like 254 by default.



Okedokey said:


> I would just restart all your routers/modems and computers.  It will sort itself out i think.



That could be. From the reset part, it sounds like it works when the router is reset. That said, having to reset the router every time you turn on your PC is a bit silly.


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## Tobias Rieper

johnb35 said:


> Well according to this image.
> 
> 
> 
> 
> 
> 
> Your gateway is 192.168.1.254
> 
> Your ipv4 address is 192.168.1.64
> 
> This is why its not getting a valid IP.  Usually a gateway will have an internal IP of say 192.168.1.1 and any devices attached to it will have an IP of say 192.168.1.101, 192.168.1.102 and so on.  There is something definately wrong with the configuration.  Can you tell me what router and modem you have?  Is it a modem and router all in one or are they separate units?



My router is a BT HomeHub 2.0 (quite a few years old now), I take it this is a all in one router and modem?

Btw, could it be one of the ethernet ports perhaps?

Ethernet Network Realtek PCIe GBE Family Controller.

I have BT Broadband Unlimited btw.

From 'speaking' with a few users, I'm getting a feeling that I might need to get a new router (BT HomeHub) from my ISP ie BT Broadband ?


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## Cromewell

Yes, that is an all in one.

If you are renting the hardware from them, a newer version is certainly an option. It might come with a cost increase.

The device you have might be ok, make sure it's fully up to date before replacing it. If you type http://bthomehub.home into a browser, scroll to the bottom and you should see the current version number. For 2.0 you are looking for one of the following:
•BT Home Hub 2.0 (Infinity) - Software version 4.7.5.1.83.2.11.2.6 (Type B)
•BT Home Hub 2.0 - Software version 8.1.H.U (Type A) or Software version 4.7.5.1.83.3.37 (Type B)

They apparently can push the updated out over their network, so if it's an older version try calling them and asking for the latest version to be pushed to you before buying new hardware.


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## Tobias Rieper

Thanks Cromewell 

Incidentally, I tried IP manual configuration. 

Because, I put my PC to 'sleep mode' then when I came back to 'wake' it up I had no internet connection.  So, I tried manual configuration for the first time. 

I will post six screenshots in chronological order of what happened.  So far, the result appears to be good.  I have my internet connection.  But, please look and comment on the stages if you can just to ensure it looks all okay.  I do notice that DHCP is now disabled (is this a good or bad thing!?), that is the only difference I can see.  Apart from that, it all looks good so far.....

I manually configured the IP settings, clicked on validate then ok.  It came up with screenshot 1, so I just hit the reset button on the router.  Screenshot 2 shows the next stage of troubleshooting - fixing the default gateway.  Screenshot 3 just highlights the next stage (I did have internet access at this point but it did state 'unidentified network'). Screenshot 4 shows ipconfig after all of this for comparison. Look where it says "DHCP enabled = no"?  Screenshot 5 I have highlighted my network connection setting again which shows internet access.  Lastly and finally, screenshot 6 is the end result - "Network Internet Access" 

So, fingers crossed, this should be okay now?  I'll post back tomorrow evening to see if there are any issues.

(1) http://i59.tinypic.com/e9cgtd.png
(2) http://i57.tinypic.com/b9cdqo.png
(3) http://i61.tinypic.com/214y2l0.png
(4) http://i60.tinypic.com/2zjjlgo.png
(5) http://i61.tinypic.com/149xeb.png
(6) http://i62.tinypic.com/2qi37dh.png

Many thanks
Goodnight
Regards


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## Cromewell

If you set that IP manually, yes you should be good to go. If you have other devices that connect you might want to pick an IP out of the range that the router tries to hand out but I doubt it will be a problem since as you noted, DHCP seems to be off most (all?) of the time.


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## Tobias Rieper

Looking here:

http://bt.custhelp.com/app/answers/detail/a_id/13073/c/346,1887,1892

To confirm, BT do this automatically over the net like you say Cromewell.

Incidentally, that link you and BT provide here: http://bthomehub.home doesn't work?


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## Cromewell

You could try http://192.168.1.254 instead. It should send you to the same place.


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## Tobias Rieper

Hi, 

Unfortunately I am having the same problem as before. Even though I have manually changed my IP settings to static and also incidentally updated my network adapter, I login from fresh and still there was no internet access. 

I had to reset my router again. I thought the manual configuration plus updating my network adapter would solve the issue but it hasn't. 

I am hoping that when my new router (4.0) arrives in a few days that this will rectify the problem as my old one is 2.0. 

But in all honesty, I am not hopeful. 

Please advise, many thanks?


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## Cromewell

Couple guesses left:

failing hardware, in which case the new one will fix it
modem is disconnecting after a certain period of inactivity, in which case it should reconnect shortly after booting - doesn't seem to be so I'm thinking this is not the case
isp is dropping the line for some reason and modem not properly reacquiring service (kind of related to #1)


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## Tobias Rieper

I'm hoping it is the HomeHub router problem.  I'll have to wait and see.

I will be shutting down my PC soon to go to bed.  In the morning I will booting up my PC as per normal and this is when it happens, always from a fresh boot, no instant connection!

I reset router and its fine. :-0 !?!?!?


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## beers

The DHCP assignment self is OK.  If you get connectivity, the default gateway can be anything but it has to match the subnet and address of the layer 3 interface (ie, router) in order to get out of your local network.

169.254/16 is an APIPA range, your PC assigned it's own address originally as it didn't get a response from the DHCP server within a certain amount of time.  The interesting part is where you had issues with a static assignment that may be indicative of other behavior.

If there's a firmware update for that router, give that a shot.  Otherwise, it sounds like it may be crapping out by not routing packets or assigning addresses until rebooting it.


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