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If there are two switches connected directly together with two links is spanning tree protocol needed? please see below snippet

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Two links between two switches form a mesh: there are multiple paths between the switches. With default/no configuration, these links cause a bridge loop, bringing down your network (broadcasts circulate endlessly, MAC tables get trashed, ...).

If you want the dual link for redundancy, you need a flavor of STP (RSTP, MSTP, RPVST) that blocks one of the links logically unless the active link fails. Essentially, STP reduces the mesh to a tree where there's only a single path between any two points.

If you want to aggregate links for performance, you need to set up a link aggregation group (LAG), preferrably using LACP.

Alternatively, more advanced switches support protocols for both purposes like Shortest Path Bridging (802.1aq) or TRILL (RFC 6325).

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Yes, of course it is needed because you have a loop. Spanning tree will pick a single path between the two switches, breaking the loop.

A layer-2 loop will cause your network to crash as it will perpetuate and amplify broadcasts until your network is overloaded. Spanning tree will determine a single, loop-free path to the root bridge, and it will block traffic on any other paths to the root bridge.

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