Question on Auto MDI/MDI-X feature 1

[mlgmartin]

Is there any advantage/disadvantage connecting 2 switches (with Auto MDI/MDI-X feature) with cross or straight cable?

"It is an equal failing to trust everybody, and to trust nobody.

 

[cajuntank]

Back in the day, one would have to create a crossover cable to make their uplinks from one hub or switch to another. Auto MDI/MDI-X feature was put into place to allow the port to electrically determine whether the cable was straight through or crossed to ensure a connection was made regardless.

So the answer to your question is, the only advantage of keeping the cable straight through is since all switches now a days support Auto MDI/MDI-X, putting a cross over cable would be a little "non-standard" and might cause headache for someone down the road since that wouldn't be something you normally look for should there be a problem.

 

[mlgmartin]

Is it true that Auto MDI/MDI-X feature only works if the port is configured as AUTO?

"It is an equal failing to trust everybody, and to trust nobody.

 

[cajuntank]

From what I remember, that is true. I have not had to worry about that for some time now since all of my uplinks are over 1Gb or 10Gb fiber, but if you are messing with external transceivers or mixed manufacturer's switches, then you might run into a situation where they just won't autonegotiate correctly with each other on speed and/or duplex; so in that situation, you would have to define your speed/duplex settings and use a cross-over cable.

If someone else has different information on this, I would like to know for reference myself.