Switch Interconnect Help

[bssmith10]

I am interconnecting four 2960 switches. Everything I read says I need to use a crossover cable, but they are working with a straight thru cable. But when I try to hardcode the ports on both ends of the cable the ports go down. this is true for both the fastethernet and the gigabit ports. Why is it working with straight thru cables, and why are the ports going down when hardcoding the speed/duplex?

[gpulos]

this switch supports automatic independent interface crossover (works as an MDI-X port which senses the cable/signal and makes a crossOver internally)

try to use crossOver cables, no matter what it looks like is working. then set the speed/duplex to your liking (the same on both sides) if they fail to connect, lower the speed settings and possibly change the duplex to half. (attempt to get the ports up with any settings to see if they are working at all)

see below link for more info:

http://www.cisco.com/en/US/products/ps6406/products_configuration_guide_book09186a00804fdc16.html

[bssmith10]

I changed to crossover cables. I can now hardcode the fastethernet ports, however the gig ports will not come up at all with crossover cables.

[glen.grant]

auto mdix---If you use auto mdix then the port had to be set as auto for it to work , otherwise you would need crossovers if you hardcode the port for speed and duplex. Here is ablurb from the guide.

Auto-MDIX is enabled by default. When you enable auto-MDIX, you must also set the interface speed and duplex to auto so that the feature operates correctly. Auto-MDIX is supported on all 10/100 and 10/100/1000-Mbps interfaces. It is not supported on 1000BASE-SX or -LX SFP module interfaces.

[bssmith10]

The gig ports are by default mdix auto. In this mode, I tried straight thru cables, and the ports come up. I configure speed 1000 duplex full on both ends of cable, and ports go down. I tried crossover cables, and the ports go down, no matter if speed/duplex is hardcoded or not.

I then configured no mdix auto. Straight thru cable does not work and crossover cable does not work. Doesn't matter if speed duplex are hardcoded or not.

The only way I can get the gigports to come up (remember swtich to switch connection) is with straight thru cable, mdix auto, and speed/duplex auto.