Works on HUB but not on SWITCH...WHY!?!?!

[summer055]

I have a homenetwork with several PCs. Here is the setup:

Cable ---> Linksys Router ---> Linksys 4 port switch ---> Linksys hub.

I have 3 lines that will not work if connected to the router or switch. But they work if they are connected to the hub. It doesn't matter what OS or PC. I took my laptop (which works in the "GOOD" rooms") and took them to each room, and it failed to work in the "problem" rooms. So I know it has nothing to with the PC configurations. I have been able to deduce that there might be something wrong with the wiring that runs from the main computer room (where the router, etc. are) to the other rooms in my house. But what I don't get is why I can connect in those rooms thru the hub, but not directly to the switch or router.

I have tried the following:

-Router Uplink connected to the Switch Uplink via straight thru and crossover.
-Router Uplink connected to a regular port switch via straight thru and crossover.
-Router port connect to Switch port via straight thru and crossover.

All scenarios had the same result. The same rooms that worked before still worked and the ones that were bad were still bad. But the bad connections were still able to get thru when connected to the hub in all cases. But I'm trying to get rid of the hub and just have the switch and router.

Does anyone have any suggestions or know what the problem could be???

Thanks,

Sarah

 

[deeno]

Wow, Sarah, that's a tricky one!! I doubt any of this will actually be of any use, I'm just as confused about this as you are. Let me just ask some questions and throw some ideas, though...

First, when you say that the bad lines can connect to the hub, do you mean they can actually communicate with other devices on the network through the hub? If you're saying they can connect simply because the lights on the hub come on then the connection may not actually be a working connection.

Next, how are your lines run? Are they simply patch cables run between the router/switch/hub and the device? Or are they run through a patch panel with outlets in the different rooms?

Anyway, best guess would have it that the bad lines, however they are run between the router/switch/hub and the rooms, are just that; bad lines. I would suggest using a line tester to verify this. If you can't get a hold of a line tester, try to rerun one of the lines. Depending on how the lines are run, you may be able to use the existing lines to pull through a new line. If you are using a patch panel with outlets in the rooms and you can't get this working, you will definitely find a line tester handy.

I also toyed with the idea that this is a problem with the 10 or 100 speed connection, but I don't see how that could be a problem. If I recall correctly, a 10 speed connection requires only 2 wire pairs, and the 100 speed requires all 4 wire pairs. If you can actually establish a working connection with the hub through the lines then I don't see how this could be a problem.

Please let us know what you come up with. I'm interested to see what you find...

deeno

 

[bcastner]

Uplink port --with straight cable-- regular port on next device.

regular port -- with cross-over cable -- regular port on next device.

Uplink port -- with cross-over cable -- Uplink port on next device (although this is sort of silly, it would work)

No other combinations will work.

 

[BOKA]

You did not mention the speed of the hub.
Both 100Mb and 10Mb require only 2 pairs (unless it is 100BASE-T4, which I doubt you have), however, split pairs will prevent communication at 100Mb.
Just like DEENO said, check your cabling, but pay attention to the pinout. Your cable may well be crimped straight-through, but if it is not pinned correctly, it will not work at 100Mb.
So, if the hub is 10Mb, it drops your link speed to 10Mb and the incorrectly crimped line works. Connected directly to the switch, which usually is 100Mb, it stops working.

Good luck.

 

[summer055]

I have not had the time to mess with my network since my post. But it is a 10mb Hub...when I say they work when connected to the hub, I mean that they can access everything on the network and the internet...I have outlets in different rooms.

Thank you for all your helpful posts. I will try to get a line tester later this week to test the lines.

Sarah

 

[bierhunter]

Just trying to get a clear picture to see if I can help.

So, you're connected as shown:

Cable ---> Linksys Router ---> Linksys 4 port switch ---> Linksys hub

With that connection, you connect a laptop to the hub and you can get to the Internet and everything. Is that correct?

If so, then your uplinks between router, switch, and hub are fine. Otherwise the traffic would never get past the hub.

So, the next question is: When you say the laptop doesn't work connected to the switch or the router. Are you changing the above connection diagram during your testing, or are the router/switch/hub all still remaining connected?

 

[bithead9]

Sarah,
What are the speed of the NIC card in the laptop/PC ? Some NIC cards do not autonegotiat WELL. You might need to manually set the speed to 10MBit and HALF duplex. Not all NIC cards are created equal. When you put a HUB inthe picture it runs by default at HALF duplex. So the NIC might be just fine.
Good luck and let us know your results...

 

[nemotek]

if you do an IPCONFIG on the command prompt what is the IP address you are getting there.?

if you are getting MEDIA DISCONNECTED try reducing the speed of the card as bithead say's it cannot auto-negotiate

DEVICE MANAGER > NETWORK ADAPTERS / right click on the adpater click PROPERTIES >clieck the ADVANCE tab.