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I'm trying to set up my home network but I have some connectivity issues with my switches. Basically the scheme is R <-> S1 <-> S2. The problem is that the two switches don't appear to be able to properly communicate. See the image, the top diagram is the desired one but doesn't currently work, and two other things that I tried so I can at least validate a few common issues.

Some more details :

  • switches are identical, model given in the diagram
  • I swapped S1 and S2, the situation is the same, switches seem to be in proper working order
  • if I replace the second switch with a PC it will work - this tells me the wire in the wall (and the outlets) are working fine
  • if I connect the switches via a direct patch cable it all works fine
  • I even switched S1 with the router itself then connected S2 to the router and it worked

enter image description here

I read that you should normally connect two switches with a crossover cable - however this is not needed anymore with the newer switches having the Auto MDI / MDIX capability. The fact that I successfully connected the two with a straight-through patch cable (see 3rd diagram) somewhat validates this.

I guess the next step is to make a crossover cable anyway and try with that but since a direct cable currently does the job I'm not sure how a crossover will change things.

share|improve this question
I think that cable in the wall is broken. It works straight through - the PC proves that (step 2), but it doesn't work crossover, and it would if it were working - that is proven by the workaround (step 3). Try replacing it. – Paul Mar 5 '13 at 12:48
It's a bit complicated to replace it (true, I should have checked better), I think I'll try to rewire one of the outlets first. – CyberDude Mar 5 '13 at 12:55
Yeah, it is almost certainly going to be the outlets rather than the cable itself, so that should work. – Paul Mar 5 '13 at 12:57

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