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New Member

connecting router to switch

i connected the fastethernet interface of my router to a switch using a straight through cable and i got a link. now, after installing an ethernet interface (which i know works fine) on my router, i move the same cable from the fastethernet port to the ethernet port and i get no link light (interface is up but line protocol is down). wehn i replace the cable with a X-over, i get the link up. i thought you only use X-over when connecting same OSI layer equipment? or do i have to add some extra commands when moving from fastethernet to ethernet interface?

I have no control over the switch, and don't even know what kind it is. all i know is that a straight through cable is droped and that is what was connecting successfully to my router until the day i moved it to the newly installed ehternet interface, then it stopped working. but when i cross my end of that cable and plug it in, it starts working? what am i missing?


New Member

Re: connecting router to switch

Here are some guesses:

Maybe the switch having problems with negotiation.

# Your FE interface can negotiate speed and duplex.

# Your E interface cant negotiate, because its only got 10Mbps/Half duplex.

# The switch maybe negotiates speed, duplex, spanning tree, IP telephone power, vlan trunking etc.

# Maybe the switch has the feature of auto mdi/mdi-x.

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