The fiber that connects the Dolphin card in the c1lsc machine (in the 1Y3 rack) to the Dolphin switch in the 1X4 rack appears to have died spontaneously this morning. This was indicated by loss of Dolphin communication between c1lsc and c1sus.
We definitively tracked it down to the fiber by moving the c1lsc machine over to 1X4 and testing the connection with a short cable. This worked fine. Moving it back to using the fiber again failed.
Unfortunately, we have no replaced Dolphin fiber. As a work around, we are stealing a long computer->IO chassis cable from Downs and moving the c1lsc machine to 1X4.
This is will be a permanent reconfiguration. The original plan was to have the c1lsc machine also live in 1X4. The new setup will put the computer farther from the RF electronics, and more closely mimic the configuration at the sites, both of which are good things.