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Switching primaries
It is important to ensure the atomicity of switching the node’s primaries for partitioning in node entry or exit scenarios, otherwise the HWM >= LWM <= HWM invariant will break, which ensures that if at least one stable copy is available, everyone else can restore its integrity from it. This is achieved due to the fact that transactions on the previous topology are completed before switching (as a phase of the PME protocol) to a new one and the situation when two primaries of a node simultaneously exist in a grid for one partition is impossible.

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