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Can ethernet travel from fiber to copper back to fiber then back to copper?

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upinflamezzz

IS-IT--Management
Oct 10, 2011
178
US
Dedicated Comcast fiber -> Cat5 -> fiber -> Cat5. I'm using 2 fiber/copper 1000 base media converters and 2 gigbit switches. I can't get a connetion on the other side. Cables are good. Dedicated fiber -> Cat5 is good. Any ideas?
 
First idea, use a laptop at each step so you know which leg is borked.

The fiber converters I have used can be set to always see link, or to see the link on the copper, choose wisely.

Unlike copper fiber runs at only one speed and only one duplex. Nothing can be set to Auto. If some stuff HAS to be auto, everything else must half duplex. You cannot mix Auto and full duplex.

I tried to remain child-like, all I achieved was childish.

Tsar of all the Rushers
 
Be sure the fibers are:
Tx->Rx
Rx->Tx

Like jimbopalmer most of the other fiber problems I have had involve link speed/duplex settings. One lot of media converters I used only worked at 100/half and the switches they were connected to had to be set to that manually.

What converters and switches are you using?
 
In addition to the TX/RX orientation of the fiber connections, the back-to-back copper could be a problem too, if the media converters are not auto MDI/MDIX on the copper side. If that is the case you need a crossover Ethernet cable between the media converters. If you are not sure about features/options of the media converter, contact the manufacturer for clarification.

....JIM....
 
I have set up copper to fibre adaptor, through to adaptor back to copper, then into a switch, back out to fiber back to copper to switch and then branch to LAN from there.

Jon
 
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