Critical Fixes:

o Fix a bug that could prevent HA from working properly in
  TrueNAS 9.10.1-U2 with certain encrypted pool configurations.

o Fix a bug that could render the updater in TrueNAS 9.10.1-U2
  inoperative.  Please contact http://support.ixsystems.com for
  assistance updating if you are affected by this bug.