PC won't connect to Internet when directly connected to UPC modem by Ethernet cable

BenEadir

Hi all,

I've been trying to get some support from UPC on this but failed.

I've 50mb fibre from UPC and prior to this the set up was one Ethernet cable out from the UPC modem into my Asus RT-N66U router which broadcasts Wi-Fi around the house but as my PC (a Dell Vostro 200 E4500 Core 2 Duo Processor 2.20GHz, 800Mhz FSB, 2MB cache 4GB RAM) doesn't have wireless I run a cable from the Asus RT-N66U router back to the PC and this has worked fine and continues to work fine. UPC support helped me set up a static IP address on my Asus RT-N66U and advised to run an Ethernet cable from the router to the PC rather than direct from the UPC modem to the PC.

I recently upgraded to 100mb and did some speed tests on laptops and the PC. The laptops operating over Wi-Fi were getting download speeds of between 70mb and 100mb which I'm very happy with but the PC was only managing 28mb. I called UPC and they got me to disconnect the PC from the router and connect directly to their modem but that resulted in "no internet access" so they then asked me to change the IP4 settings from "automatic" to some predefined settings and that also resulted in "no internet access". They asked me to repeat the exercise with an old laptop i.e. connect it directly to the UPC modem via an Ethernet cable, implement the settings they gave me in IP4 and off it went getting up to 90mb download and 10mb upload. Once that worked UPC (in fairness to them) said that their responsibility ended at that point and suggested I call my IT department (don't have one!!) or Dell which I just know will be a waste of time.

Apologies for the log winded post. I know I can revert to connecting the PC to the router and continue with a 30mb download speed which I know is fine but it's bugging me that I can't get the PC to connect directly to the UPC modem to take advantage of the full speed I'm paying for and/or get the PC to get the full speed via the old Ethernet connection to the router. I can understand why there would be degradation of performance over Wi-Fi but I can't for the life of me understand why an Ethernet cable bringing 100mb download speed into the Asus RT-N66U router is degraded to 28mb when it comes back out via Ethernet cable, especially as both the inbound and outbound Ethernet cables are less than 3m long!!!

If you've been patient enough to read through this post perhaps you have some experience you could share with me or suggestions you could make so I can get my PC to take advantage of the speed I'm paying for.

Cheers,

Ben

Skalragg

Hi Ben

Personally when troubleshooting I try to isolate possible causes as much as possible.

UPC ... To my shock and horror actually tried reasonable steps....


In your case I would remove the router used for wifi from the equation for purposes of testing. Plug in PC into the UPC . Router nod go to ipv4 settings. See what ip u are receiving via dhcp using ipconfig on windows command line / ifconfig if the machine is a mac



Please screenshot/ report what you are getting back. If you can now get. Internet access what speed test are you getting...


If no internet access appears to be available see if you can ping the gateway IP address listed in your ipconfig/ ifconfig command

Theoretically on a router ( when using switch interfaces connecting to other switch switch interfaces in router / access point may cause problems without a crossover. Most modern equipment carry the slack and allow it to work...



Anyway fist step is to establish is the fault ur PC/ UPC router or other one try the first step

BenEadir

Thanks Skalragg,

I'll try those steps tomorrow and report back what the outcome is.

BenEadir

Skalragg wrote: »

In your case I would remove the router used for wifi from the equation for purposes of testing. Plug in PC into the UPC . Router nod go to ipv4 settings. See what ip u are receiving via dhcp using ipconfig on windows command line / ifconfig if the machine is a mac

Please screenshot/ report what you are getting back. If you can now get. Internet access what speed test are you getting...

If no internet access appears to be available see if you can ping the gateway IP address listed in your ipconfig/ ifconfig command

Hi Skalragg, I eventually got round to this. Lost UPC BB in my area for 3 days right after your post above (!!!) and have been flat out with work more or less since then.

I now have an Ethernet cable going directly from the UPC BB modem into the PC and IPv4 settings are set to automatically detect IP address and DNS server settings automatically but I'm not getting any internet access at all.

I ping'd the three IP addresses which IPCONFIG returned and 255.255.255.0 failed.

See



I'd really appreciate any help you can give me to get this sorted.

Ben

ED E

You cant ping a subnet mask (255 255)

Pinging yourself, 189, is a little pointless.

The ping to the router at .1.1 shows the link between the PC and the router is ok. But you arent getting out past that. Its probably a software issue on the PC at that point if access works for other devices.

What happens when you ping upc.ie?

Do you have any firewall software running? VPN? Tor? Proxy service?

Also, is that vostro running vista? If its coming up as "unidentified network" that could be one of vistas flaws.

Skalragg

ok, so looking at that, you can ping your gateway using the address that DHCP on the UPC modem gave you.

Next step is can you access the internet with that setup ? browse to a site, if that doesnt work ping 8.8.8.8 / google.ie

If you can then DHCP is working correctly on your UPC modem and perhaps UPC gave you the wrong instructions during testing.

Come back to me with results of that....then we can look into speed etc. as there are a few things that can cause issues.

Also FYI. first address you pinged .189 is your PC's address, 255.255.255.0 was subnet which basicially defines how many IPs are in the same 'range' and 192.168.1.1 is your gateway. only one thats important is gateway . what you can do is if you can NOT connect to internet but can ping 8.8.8.8 then your DNS settings are an issue.

BenEadir

Skalragg wrote: »

ok, so looking at that, you can ping your gateway using the address that DHCP on the UPC modem gave you.

Next step is can you access the internet with that setup ? browse to a site, if that doesnt work ping 8.8.8.8 / google.ie

If you can then DHCP is working correctly on your UPC modem and perhaps UPC gave you the wrong instructions during testing.

if you can NOT connect to internet but can ping 8.8.8.8 then your DNS settings are an issue.

Hi Skal,

Not sure why/how but after doing the ping process (two of which demonstrated my complete ignorance of this subject matter! ) I'm now able to get internet access with IPv4 IP and DNS settings set to Automatic but performance is still way below what I can get from an old laptop connected to the same Ethernet cable.

I'm getting 32mb download and 11mb upload using the Ethernet cable (which is the same performance via the Asus router) but when I plug an old Dell laptop into the cable I can get 70mb download and more or less the same 11mb upload.



My PC is a 3 year old Dell Vostro 200 E4500 Core 2 Duo Processor 2.20GHz, 800Mhz FSB, 2MB cache 4GB RAM running Windows Seven Home Premium 64 bit whereas the 5 year old Dell Vostro laptop is running Win 8. I guess the network card in the PC could be constrained in some way although if anything I'd expect the network card in the old laptop to be lower performance than a 3 year old PC!!

Ben

Bog Standard User

bad network driver.. update your nic driver

BenEadir

Bog Standard User wrote: »

bad network driver.. update your nic driver

Thanks BSU, how would I go about doing that? I'm not familiar with what an NIC driver is

Ben

ED E

BenThere wrote: »

Thanks BSU, how would I go about doing that? I'm not familiar with what an NIC driver is

Ben

Grab your service tag off the casing and put it into support.dell.com. Thatll give a list of drivers for your specific PC and then find the one market ethernet in the networking section.

BenEadir

Thanks Ed, I'll do that.

Ben

BenEadir

Hi Guys,

I'm back with more LAN/IP problems I'm afraid - apologies

So I decided to tidy up and standardise my cables and purchased some nice new CAT 6 cables. I powered off the PC, powered off the UPC modem and powered off the ASUS WiFi router before removing all the old cables and replacing them with the nice new CAT 6 cables.

On power up I was back to the familiar "No Internet Access" situation with my PC but the ASUS router is throwing out powerful WiFi (100mb down and 10mb up) to all other devices.

I decided to plug the CAT 6 cable direct from the modem into the trusty old Dell laptop which previously had no problem and it too is now returning "No Internet Access" even though it's fine when connected via WiFi.

Here is a screen grab of what I'm getting from ipconfig on the laptop



I think I need to configure the LAN IP and DNS settings as they are both set to automatic on both my PC and Laptop but I'm afraid I haven't a clue what to to and would really appreciate some more assistance. I promise I'll both learn as much as I can and leave the set up alone one I have it back up and running!!!

Ben

Cuddlesworth

What type of UPC router do you have? Your set-up is pretty poor, your most likely running double NAT or possibly two DHCP servers across the same subnet which would explain the intermittent problems. I'm going to write up the below assuming you have the basics of viewing IP's and connecting to the management webpages from you past posts.

Firstly, make sure none of your laptops/desktops have static IP's assigned. All should be on DHCP.

I have the same router and I would recommend doing the exact same thing as me. Turn your UPC router into a bridge, effectively making it a modem only. You can do this with the Cisco boxes. Check the broadband forum for instructions. It kills the webpage and most of its functionality once its done but you don't need that really since you have a good router, you don't need 2.

Then wire from a Lan port on the UPC router to the "WAN" port on the ASUS box. I'm being very specific about this, make sure its going into the Ethernet connection that's on its own. Make sure the ASUS router is set to DHCP on the WAN interface if your doing it this way. Easiest way is to reset the router to defaults to make sure of this, since you say UPC "helped" you configure it I'm not sure if they go you to change anything else. WAN, NAT and UPNP should be enabled on the WAN page.



If you don't have a Cisco box that can bridge, its a little more complicated. You need to wire up the Asus box the same way as above, into the WAN port on the ASUS from the UPC modem. Your UPC box should be assigning IPs with something like 192.168.1.x(x = 2-255) and the modem itself should have a IP ending with 1. You statically assign a IP within this range to the WAN port of the Asus router in the WAN settings page on the left. Change the menu at the top of the WAN page to Static, IP 192.168.1.2, subnet 255.255.255.0, gateway 192.168.1.1, DNS1 8.8.8.8 DNS2 8.8.4.4. I'm ending the IP with 2 for simplicity.

During the above, you should only be able to talk to the UPC router webpage if connected to it directly, the same with ASUS. You should not be able to talk to both at once if its set up the way I think it is.

Connect back into the UPC modem. Then find the DMZ settings on your UPC modem, set that IP for DMZ mode. This will help with various programs you might use. I'd recommend at this stage disabling wifi and the firewall. It should be much more stable that way and provide less interference for the ASUS box.

Now for the important bit. Connect to the ASUS router and check the IP its assigning. If its the same IP range as the UPC box and its WAN port, you will need to change the subnet its using. So for example, if the UPC modem is giving out IPs starting with 192.168.1.x and the ASUS box is giving out IP's with 192.168.1.x you have a problem. Go into the lan menu on the ASUS router and change the IP on the box to (example) 192.168.2.1, subnet 255.255.255.0.

You should have internet access now, but you might need to disconnect and reconnect to the ASUS box. You should at this stage be able to talk to both webpages too, 192.168.1.1 for UPC and 192.168.2.1 for the ASUS.

BenEadir

Thanks Cuddlesworth, that's very comprehensive. It may be beyond my ability to implement but I'll have a go when I get home this evening.

Cheers, really appreciate it.

Ben

BenEadir

Hi Cuddlesworth,

Turns out my UPC modem was already bridged to the ASUS Router so the only way I could get Broadband to my PC was to run an Ethernet cable from the ASUS Router to the PC and set the IPv4 settings to Automatic.

I tried running a cable from the UPC modem direct to the PC (which would be my preference) but no matter what I tried I couldn't get it to work. I called UPC support and they suggested a few different IPv4 settings but none of them worked either so they too advised me to go with the cable from the router which is a bit of a pain as it uses a port on the router I would prefer to use for my sons PS4 and it looks untidy having a cable running from the modem (which sits on top of the PC) up to the router which is loated on a high shelf so it throws WiFi round the house and another cable back down again to the PC. I had a nice 50cm CAT 6 cable I'd hoped to use directly from the UPC modem to the PC but I guess that's now excess to requirements :mad:

Thanks for your help.

Ben

Cuddlesworth

It seems unlikely that UPC would actually enable bridge mode on the UPC modem. And if they did, three devices can work off of it so that doesn't make sense. At this stage I'd say get somebody over to reset everything and start again.

For you desktop, you only have a 100mb nic on that. Odds are its of a horrible quality and your low speeds are a result of a firewall/hard-drive/nic combination.

BenEadir

Cuddlesworth wrote: »

It seems unlikely that UPC would actually enable bridge mode on the UPC modem.

Yeah, I was surprised myself but they did. I recall a couple of years ago having a problem with Wifi dropping off and the helpdesk guy in UPC was really very helpful. Even though 3rd party routers aren't their responsibility he diagnosed that the router I had then had a fault (some sort of overloading/over heating) and when I googled it I found lot's of users of that model had the same issue. The UPC guy recommended the ASUS RT-N66U as I have over 20 wireless devices in my house and he offered to set it up for me. I bought the router from Amazon and true to his word he set it up for me with a static IP address etc as that was important to my son who was playing a lot of xBox at the time and needed a static IP address.

The router settings haven't changed since (I wrote them down at the time and they remain as originally set) so I'm guessing there is something wrong with the UPC modem setting as neither my PC nor my old laptop can get get internet access when connected to it directly either via automatic DHCP or manual settings.

Could the fact manual settings don't work be down to the fact that Manual Assignment isn't enabled in my LAN - DHCP Server setttings?



Ben

Cuddlesworth

Can I see the WAN page on the left hand side and the Lan IP page on the top left?

BenEadir

Cuddlesworth wrote: »

Can I see the WAN page on the left hand side and the Lan IP page on the top left?

Thanks for the offer of more help Cuddlesworth but I got it all sorted. Called UPC who were happy to issue me with a new range of static IP addresses. One to be used on my ASUS router and one to be used on the PC I was connecting directly to their modem. Once I changed the static IP address on the ASUS router and input the settings onto the PC I was in business plus I now have 3 more static IP addresses I can use if I need to plug more devices into the UPC modem and on top of that a WiFi extender I had been having terrible problems with (performance would randomly go from from 15mb download to less than 1mb download or nothing at all) now seems to be holding 22mb download consistently, or at least for the last half hour anyway.

Fingers crossed this solves my problem.

I've learned a bit over the last two days I can tell you. Interesting stuff.

Thanks again for your help.

Ben

Cuddlesworth

Just for curiosity sake, what was the fixed IP they gave you.