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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.
Dip switch 1 is auto-negotiation of speed and duplex and that was left enabled=UP. Set switches 2, 3 and 4 DOWN on both converters,
to disable pause control, link pass-through and far-end fault.
Pause control should be enabled if ALL devices attached to the media converters have it. I didn't know if the ethernet switches have it, so I disabled it (dip switch 2 DOWN). I now think that was a mistake and that all modern ethernet switches have pause control. So I suggest that we set switch 2 UP on both units, and power cycle them on the next visit.
Dip switch 1 is auto-negotiation of speed and duplex and that was left enabled=UP. Set switches With 1=UP, and 2,3 and ,4=DOWN on and power cycling both converters,
to disable pause control, link pass-through and far-end fault.Link units, the link came back and we could ping the seatainer. Swapped data boxes and then couldn't ping. Eventually power cycled the 5 port switch at the tower and things worked again.
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