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Swarm changes a volume's state to Retiring when any of these events occurs:
Retire is clicked next to a volume on the node status page in the Swarm UI (or the legacy Admin Console).
Retire Chassis/Node is clicked, which retires all volumes on the node at the same time.
The number of I/O errors specified by disk.ioErrorToRetire occur in the time period specified by disk.ioErrorWindow.
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