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The manual for the converters (Transition Networks, model E-100BTX-FX-05) describes the dip switch options. I've cut and pasted some of the manual to the end of this entry. It seems that we should disable the pause control, link pass-through and far-end fault options on both converters. Link pass-through and far-end fault options can cause a copper interface to be disabled if a fault is detected on the remote copper interface or on the fiber. These options appear to be for a building network with good network monitoring equipment. Perhaps a power outage, cable disconnect, or powering down a network switch could cause the converters to think there is a fault in the copper line, and then the copper interfaces would be disabled. The manual says nothing about whether the interfaces are automatically brought up if the fault disappears.
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