From the Cointerra user guide.

"To boot up the TerraMiner IV connect the power cords within 3 seconds of each other. If they are not both powered up within this time it is possible that the BeagleBone controller card will not recognize both GoldStrike boards inside the TerraMiner."

There is a ton of detailed status information that can be seen in the Advanced/Stats page.  You can see the performance of each of the 8 cores on each ASIC including, hardware errors,  voltage and temp.    I have seen issues with one core on each ASIC that have shown as low voltages and hardware errors.   Right now seeing no issues on any cores.  Not sure if these were intermittent issues or perhaps some temp related issues on the first day of operations.

I am managing a Cointerra for the first month of its life.  I have the two plugs running off of two separate 110v circuits, which they recommend as well.   You can try unplugging and replugging as a restart. (I have done a few of those type of restarts) You also have have the small hardware reset button on the front panel that you can press with the end of a paperclip.  (I have done a couple of those restarts)

Due to Eligius stats collection and reporting issues, I couldn't get a new payout address on Friday.  So for the first 3 days I had the Cointerra paired up with an Antminer to the same payout address on Eligus so I could get at least some reporting from Eligius.  The actual hash rate gain from the Cointerra was about 100 to 200 GH less on Eligius than the 1.6 TH what I was getting reported locally.  I finally switched the Cointerra over to a separate address on Eligius a few hours ago and the Eligius stats are now looking better.  1.56 TH reported on Eligius and 1.62 TH locally.  Need to build up more long term stats on Eligius of the unit by itself before I can say anything conclusive.