all lines on both OBIs are Google Voice .
it is connected to my router via a switch.
Depowering the switch doesn't bring it back.
It will come back if I unplug the Ethernet and replug it or depower the OBI.
It has worked for a long time. It now goes offline about 1/day.
When it goes offline the switch doesn't see it.
Other lines connected to the switch seem OK.
The OBI config hasn't changed.