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NZHawk
09-12-2010, 02:25 PM
There are two computers hard wired to a wireless router.
The adsl modem is wired to the wireless router.
One of the computers has internet connection the other not.
It says the cable is disconnected
Changing the ports & cables made no difference.
Connecting the adsl modem directly to the computer works.
LAN setting on both computers are identical.

Purchased a new combined adsl/wireless router.
Connected it to the previously unconnected computer
Resulted in the same no internet connection - says the cable is disconnected

Can anyone suggest how to approach resolving this?
The computer is at another location so I wont be able to implement & report back quickly.

Thank you

dugimodo
09-12-2010, 02:55 PM
It's possible you need a crossover cable, I'd be surprised if that worked though.

You go from ethernet port of a modem to an ethernet port of the wireless router which I assume has 4 or more ports and then from those other free ports you connect two computers once of which doesn't work. Is this correct ? sorry but I'm scratching my head and just wanted to be sure I had it right.

If swapping connection from the working pc to the other doesn't fix it then something weird is going on. Most modern routers / switches auto negotiate and don't need crossover cables but it's possible the ethernet card or router doesn't support this. Bit of a shot in the dark.

utopian201
09-12-2010, 03:23 PM
Connecting the adsl modem directly to the computer works.
LAN setting on both computers are identical.


Does this work on both computers? If one computer says cable disconnected with either the modem, or combined adsl/wireless router, or cross over cable to the other computer, i'd say something is wrong with the cable or the NIC.

NZHawk
09-12-2010, 03:35 PM
I tried a different cable - but still was not recognized.
Plus the same cable worked when I connected the computer direct to the adsl modem

NZHawk
09-12-2010, 03:41 PM
It's possible you need a crossover cable, I'd be surprised if that worked though.
This is a good idea but - the connections all worked a week ago - something had to change.

You go from ethernet port of a modem to an ethernet port of the wireless router which I assume has 4 or more ports and then from those other free ports you connect two computers once of which doesn't work. Is this correct ? sorry but I'm scratching my head and just wanted to be sure I had it right.
This is correct - just to repeat cable from the adsl modem to the internet port on the wireless router - then 4-ports available to cable computers - I tried all of the ports - and the computer in question still showed no connection - but the one that did connect - connected through all the ports????


If swapping connection from the working pc to the other doesn't fix it then something weird is going on. Most modern routers / switches auto negotiate and don't need crossover cables but it's possible the ethernet card or router doesn't support this. Bit of a shot in the dark.
What baffles me is why does a direct connection to the adsl work?

wainuitech
09-12-2010, 03:45 PM
What Firewalls are on the one that doesn't work ? Try turning them off, or uninstalling if a third party FW.

And what OS ?

While this may or may not be the case, I had the exact same problem, and tracked it down to a faulty Router. My PC, and all the workshop PC's worked fine, my sons was intermittent. Over a period of two days slowly they all dropped off. Put in a New router and alls well.

NZHawk
09-12-2010, 03:58 PM
What Firewalls are on the one that doesn't work ? Try turning them off, or uninstalling if a third party FW.
N360 - but why did it work before and why does the direct connect work? I will still try this.
And what OS ?
Windows XP Home

While this may or may not be the case, I had the exact same problem, and tracked it down to a faulty Router. My PC, and all the workshop PC's worked fine, my sons was intermittent. Over a period of two days slowly they all dropped off. Put in a New router and alls well.
I tried a brand new combined wirless adsl router - and got the same results.

utopian201
09-12-2010, 04:31 PM
I tried a different cable - but still was not recognized.
Plus the same cable worked when I connected the computer direct to the adsl modem

Use computer A and B, since it can be confusing which computer you are referring to; A can be the working one, B can be the faulty one.

Please state if you have tried the following since it is not clear from your posts:
1. do -both- computers work when connected directly to the adsl modem? (obviously you can only test one at a time)
2. do the lights on the nic come on when the computers are connected to each other via cross over cable?
3. When A is connected directly to the modem, what kind of cable is it using?

NZHawk
09-12-2010, 04:50 PM
A can be the working one, B can be the faulty one
Please state if you have tried the following since it is not clear from your posts:
1. do -both- computers work when connected directly to the adsl modem? (obviously you can only test one at a time)
yes

2. do the lights on the nic come on when the computers are connected to each other via cross over cable?
Computer A yes; Computer B no

3. When A is connected directly to the modem, what kind of cable is it using?
Cat5

utopian201
09-12-2010, 05:16 PM
[/I][/FONT][/B]3. When A is connected directly to the modem, what kind of cable is it using?
Cat5

I meant is it a straight through cable, or cross over? Also when the adsl modem is connected directly to A or B, is the same cable used in both cases?

That is strange, that when computer A is connected to computer B, the lights are on for A, but not for B...

NZHawk
09-12-2010, 05:28 PM
I meant is it a straight through cable, or cross over?
Straight
Also when the adsl modem is connected directly to A or B, is the same cable used in both cases?
No but I tried both, switching one to the other with the same results

southern_jas
09-12-2010, 06:02 PM
I'm sure this has already been looked at both both machines haven't been manually assigned the same IP address have they?

NZHawk
09-12-2010, 06:06 PM
No they are set to automatic assign by DHCP

Speedy Gonzales
09-12-2010, 06:08 PM
Is the first option under the power management tab (under one or both NIC'S in device manager ticked)?? If it is, untick it. I had a similar prob with this the other day. ADSL kept turning itself off on this.

Everytime, I tried to connect it said the DNS servers existed but werent responding. I thought the prob was with Telstra's DNS server ips I'm using.

But, since I've unticked the above option. I havent seen the ADSL LED on the router turn off

NZHawk
09-12-2010, 06:14 PM
Thank you - I'll look at this setting.

utopian201
10-12-2010, 10:09 AM
I'm sure this has already been looked at both both machines haven't been manually assigned the same IP address have they?

I think it has nothing to do with ip settings etc. The main issue is that the lights on the NIC don't come on when A is connected to B.

Are there any auto cross over settings on comp B that can be set? My reason for this is that when A is connected to B using a cross over cable, A's NIC lights are on, but B's aren't.

Also try a straight through cable between A and B - the lights should not light up for either.

NZHawk
10-12-2010, 10:24 AM
Just a thought.
But, I was getting the same results with the new adsl wireless router.
I would have a tendency to think that the problem is with the computer.
But if that is true why would a direct connection with the adsl modem work?

pctek
10-12-2010, 10:45 AM
There are two computers hard wired to a wireless router.
The adsl modem is wired to the wireless router.
One of the computers has internet connection the other not.
It says the cable is disconnected
Changing the ports & cables made no difference.
Connecting the adsl modem directly to the computer works.
LAN setting on both computers are identical.



LAN setting - it's on AUto? Not manually set to an IP address?

NZHawk
10-12-2010, 10:46 AM
yes - auto

utopian201
10-12-2010, 11:42 AM
Just a thought.
But, I was getting the same results with the new adsl wireless router.
I would have a tendency to think that the problem is with the computer.
But if that is true why would a direct connection with the adsl modem work?

You said you were using a straight cable to connect the modem to the computer. Normally, I think a modem to computer would need a crossover cable (unless they have auto cross over detect). I think a cross over cable is needed because my modem is plugged into my router's wan port with a straight cable.

Have you tried:
1. A straight cable between A and B?
2. a cross over cable between new router and B? (I'm assuming a straight through cable between B and router failed as you mentioned earlier)

The fact that the lights on the NIC do not light up indicates a physical problem with either the cable or the connector (such as crossover mix ups etc).

NZHawk
10-12-2010, 11:49 AM
Ok I follow you.
I will give it a try - wont be until later this afternoon as it's at another location.

Thank you

dugimodo
11-12-2010, 07:58 AM
Something else that occurs to me is what speed are the ports on the various devices ? if one of the PC's is using an older 100M nic it may have trouble talking to a Gigabit device, although they are supposedly compatible problems can occur.

Also and this is a little tricky - if you have GigE capable devices at both ends of a cable that has only the 100M connections working (ie pairs 1&2, 3&6 but not the other 4 wires or even just one of them is faulty) it won't auto set it self to 100M and work because both ends detect the capability to run at gig speeds and the connection fails. An example at my place is a pc running over a 20M 2 pair homelan cable that has to be plugged into a 100M port on the modem to work and wont work on a GigE port of my switch.

If you think it's speed related you can try forcing the connection to 100M abd that may help.


A few notes about crossover cables.
1. Normally not needed as most NIC's auto crossover
2. There are two basic categories of device on a network DCE & DTE (data communication Equipment and data terminating equipment)
DCE = Modems, Routers, Switches etc
DTE = mainly the Computer itself but some other devices also are DTE
Cabling DCE to DTE = straight cable
Cabling either DCE to DCE or DTE to DTE = crossover cable. The exception to this is when using a router's dedicated WAN port (uses other names) which is already crossed over.

A simple way to think of it is any device intended to connect directly to a PC is probably configured to use a straight cable (ie is a DCE) so the connection to a modem or switch should not normally need a crossover, but the connection between two routing / modem devices should when not using a special port. Likewise a pc-pc connection needs a crossover.

wainuitech
11-12-2010, 09:04 AM
Wayyyyyyyyy back in post#6 I asked whats the OS -- Still not answered ?

Just a few Possible reasons for not working:

Your TCP/IP stack or Winsock could be corrupted, to fix that,(hence asking what OS) ;) open a command prompt, type in the following commands to suit what ever OS you have:

Reset WINSOCK entries to installation defaults: netsh winsock reset catalog

Reset IPv4 TCP/IP stack to installation defaults. netsh int ipv4 reset reset.log

Reset IPv6 TCP/IP stack to installation defaults. netsh int ipv6 reset reset.log

Reboot the Computer -- this will rebuild them.


One "odd occurrence" I had sometime back:

Lack of power to the router, and its failing under the load of two or more connections -With the working A PC going, try attaching another PC or laptop (other than B) and see if that does the same thing, or Disconnect A and only have B attached -- Does B now work ??
If so then the problem could be the power outlet is not supplying enough power.

IF you have Vista or W7 Disable IPV6

If still not working, with B connected ( but not working) open the Command prompt - type in ipconfig /all - post back the results -- then connect the modem so it is working, and repeat.

Edited: just a thought, one real easy test, with both A & B connected, boot PC B with a Ubuntu Live CD, see if the connection works.

If it does, then its a software problem in Windows on B, if not then its the router not supplying the connection.

NZHawk
13-12-2010, 04:21 PM
My apologies for not answering regarding the OS: Windows XP Home.

Let me re-describe the situation for possibly better clarity. (Forgetting previous problem description)

- Windows XP Home computer
- D-Link ADSL modem (DSL-320G) connects & works - no problems
- Dynalink ADSL2 + Wireless 4 port modem (RTA1025WV6) – shows that the cable is not connected
- tried a cross patch cable with the same results – cable not connected
- moved the - Dynalink ADSL2 + Wireless 4 port to another computer & it works just fine – so this comfirms the Dynalink works

Will try the Ubuntu boot Tues after 3pm and report back

SolMiester
13-12-2010, 04:29 PM
You have tried both cables between router and dynalink to rule out the cable yes?
Okay, silly question, but the dhcp range is more than 1?....

Speedy Gonzales
13-12-2010, 04:33 PM
Umm so why use the 320, if the RTA1025WV6 is a wireless modem/router with ports as well?

NZHawk
13-12-2010, 04:34 PM
we're replacing the 320.
with the dynalink

and yes I did try both types of cables

NZHawk
15-12-2010, 05:00 PM
Update: installed a new ethernet card and all systems work!
The computer identified that the cable was plugged in, was able to browse the internet etc.
took the network cable out & plugged into the lan on board - nothing - cable not connected
reconnected to the pci network card - worked!

I would prefer to eliminate the pci network card if I can fix the on board lan.

any suggestions? thank you.

Speedy Gonzales
15-12-2010, 05:06 PM
Well the onboard NIC is either dead or disabled. If its enabled then its dead, or faulty.

NZHawk
15-12-2010, 05:09 PM
I would agree with you but
when I connect the dsl modem to it (the lan on board) it works perfectly fine.

wainuitech
15-12-2010, 05:24 PM
As I mentioned back in #23 --- Connect the cables so its not working (onboard) Boot the PC from a Ubuntu live CD, (this bypasses Windows) if you then have a working connection then its a windows software problem, if not then its hardware.

I have seen that happen before - install a seperate Ethernet card and it works -- Onboard wont, reinstalled Windows, or rebuilt the TCP/IP stack and it worked again.

NZHawk
16-12-2010, 08:51 AM
Sorry - do recall that suggestion.
Will implement & report back.
Thank you