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STP and 3550 IOS based switches

Is it possible to create a box type loop with 4 switches, rather than the triangle type with 3 switches, and use STP to block on the appropriate leg so the traffic takes the shortest path to one of the switches being treated as a core??? In otherwords SW1 connects to SW2 and SW3, while SW4 connects to SW2 and SW3......trying to make a redundant path mainly for failover if one pair of the fiber gets...I have defined a root and a 2nd, but one of my ports err-disables......Any ideas???

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Re: STP and 3550 IOS based switches

You can create a box loop. What you have to design is how you want the traffic to flow. Then set the stp priorities according to that. Then you have to make sure that all the interfaces are the same type 100mb or 1000mb and are if possible plugged in to the same port on each switch, port one on each switch. The error disabling maybe due to a cabling issue, I would verify that link. Check out this link;

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