Cat5 wiring problem?

[sdrevik]

I have been struggling with installing my Linksys 4-port router alongside my cable modem. I have several network jacks through the house and a "patch panel" downstairs. I can make direct connection to any of my PCs if plug any of the patch cables (one at a time) into the cable modem, but if I try to put the router in to share the connection, no luck.

I have cycled power in various orders (cable modem first, router first, etc). My ISP confirmed that the cable modem is getting an IP address.

Now here's the funny part- if I plug the cable modem into one patch panel connection, and then RIGHT BEFORE THE PC (upstairs), I put the router in, it works OK. What could there possibly be about the wiring (a straight through connection!) that would make a direct connect to the cable modem OK, but flummox the router???

(I even reterminated everything to make sure...)

 

[sdrevik]

Just thought of something- it's 10M out of the cable modem, but 100M out of the router. Could it be that the haul from downstairs to upstairs just won't do 100M? I am using Cat5e cable, good terminations, but off-the-shelf Radio Shack wall terminations. That would explain why I can raise the router locally, but not while it' in the basement (if I remember correctly). Is there any way to "convert" 100M to 10M? No setting on the router...

 

[daronwilson]

The cable from the cable modem should be a straight cable into the WAN port on the router. I don't believe you have a cabling issue, sounds more like setup, but let's test like this:

Modem plugged into the router WAN port, and then verify that you have the proper LED indication on the WAN port of the linksys router. It should show a connection to the modem.

Next patch one PC in and see if you get an LED or two on the router for the port that you plugged the PC into. You should have one LED for 10 Mbs, and 2 LED's for 100 Mbs if I remember right. Assuming that you have that, we can guess that your cabling is working.

Go to that PC, depending on your OS run IPCONFIG or WINIPCFG and make sure that you have an IP address that starts with 192.168.X.X. If you are using DHCP the router should have assigned your computer a valid address like 192.168.1.2. Go into the network settings on the computer, make sure the default gateway is set to 192.168.1.1 (assuming that is the address of the router).

Next run COMMAND from run prompt, type PING 192.168.1.1 and see if you can get a response from the router. Assuming you do, close that window and open your browser, point it at

http://192.168.1.1

and you should get the login screen in the router.

Assuming that all goes as planned, depending on your modem, you may try to point your browser to it and check configuration there. Motorola bitsufers are generally 192.168.100.1 I think so see if that works.

Now if that all works, you should be ready to get online.

Do this quick check if you would, check the LED indications, and let us know where this breaks down and we'll be of more help.

Good Luck!
It is only my opinion, based on my experience and education...I am always willing to learn, educate me!
Daron J. Wilson, RCDD
daron.wilson@lhmorris.com

 

[sdrevik]

Yes, I should have said more about the LEDs. The Cable Modem is giving me a link light ("PC&quot, and the cable modem is patched to the WAN port on the Linksys, with a green light there. I also get a green light on the router, and link lights on the PC. The PC network status indicates 100 Mbit connection enabled, so I have everything short of getting packets through. No ping to the router. I'll try the Gateway setting (although that wasn't in any of the router literature). This is Windows XP on one machine and W2K on the other.

 

[sdrevik]

Well, the router definately getting and issuing IPs.. I took the laptop downstairs, and was able to surf through the router from there. It seems to be related to running 100Mbit through the downstairs->upstairs wiring. I can't ping the router from upstairs. It doesn't justify buying a cable tester!!!

I'll try changing my PC adapter to run slow.

 

[daronwilson]

If you can't ping the router, but you have a link light, I don't think it is cabling unless you truely did not terminate pins 1/2 on a pair and pins 3/6 on a pair. If you DID NOT put them on pairs (white/orange for example) I would say you didnt terminate properly and that will mess up 100 Mbs for much of a distance. But, you said you terminated it properly.

Of course, the troubleshooting rules, only change one thing at a time and then test again. So, if you can ping the router from downstairs with the laptop, then you bring it upstairs and plug it into your cable and you can't ping it AND you have a link light, I would guess the wiring is not done correctly.

Sounds like you got it surrounded though, just close in on it and fix it!

It is only my opinion, based on my experience and education...I am always willing to learn, educate me!
Daron J. Wilson, RCDD
daron.wilson@lhmorris.com

 

[franklin97355]

It would seem to me that it IS a cabling problem if the computer can connect to a port on the router directly but can't connect to the same port through the wiring.

 

[sdrevik]

I posted this earlier but it didn't take- I became convinced as well it was a wiring question, and recalling that the cable modem is 10Mb and the router is 100Mb, the problem seemed to be related to either the router and the cabling, or 100Mb and the cabling. I slowed both computer NICs down to 10Mb, and it works like a charm. I'm guessing that it's the Shadio Rack panels on the wall plates that won't support Fast Ethernet.

Problem Solved! Thanks to all.

 

[daronwilson]

Well I want to know. Were they cat5 jacks and did you use cat5 cable? I don't particularly like radio shack parts, but they should work at 100 mbs if they are cat5. Just curious...
It is only my opinion, based on my experience and education...I am always willing to learn, educate me!
Daron J. Wilson, RCDD
daron.wilson@lhmorris.com

 

[sunco]

to connect your linksys modem you go from your dsl modem to the wan connection on the linksys the link light should activate( if not use a crossover cable). Then connect the pc's in one at a time link light should activate when you plug each computer in. If still can not connect and all the link lights are on power off and on the modem. If it still does not work you may have to register the mac address of the router with your service provider.

hope this helps