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New Member

Uplink with straight through or Cross over

I am trying to uplink and form a etherchannel between the 3750 regular ports and 3548 regular ports. Could you please any one advise which cable I should be using ?

Note:When I was trying to uplnk 2960 to 3750, it worked with straight through.

5 REPLIES
Hall of Fame Super Blue

Re: Uplink with straight through or Cross over

Switch to switch traditionally meant you needed a cross over cable. Nowadays the switches can auto sense the cable and compensate so that's why your 2960 to 3750 worked.

However the 3548 is a considerably older switch and i don't think it supports auto mdix. So go with a cross over cable.

Jon

Super Bronze

Re: Uplink with straight through or Cross over

As Jon notes, newer switches often support auto mdix and should work with either cable type. Don't believe you need an auto mdix device on both sides of a link for it to work. I recall(?) on 3750, though, if "auto" isn't configured for speed/duplex, auto mdix isn't enabled.

Purple

Re: Uplink with straight through or Cross over

Joe is correct 3750 supports mdix and you can use either cable "as long as the speed/duplex on the 3750" is set as auto , obviously you want the other end as auto also .

New Member

Re: Uplink with straight through or Cross over

Thanks for your reply.

Why I asked this question because the uplink from 2960 to 3750 with Cross over cable in the etherchannel group does not work. I dont know why. It only works perfectly with Straight cables. I am going to test 3550/3548 to 3750. Hopefully it should work with cross cables.

Hall of Fame Super Gold

Re: Uplink with straight through or Cross over

Traditionally, you should use Cross-Over cable. But since MDI/MDIX is cheaper by the ton, the 3750 is MDI/MDIX capable.

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