Texas Memory Systems RamSan-300/320 - Manual (Page 79)

Secondary (Active, Primary is X)
This state indicates a secondary controller that has taken over for a
failed primary controller. The administrator originally configured
this controller to backup the primary controller; however, when the
primary controller failed, this controller became an active copy of
the primary. In this state, the primary controller backs up this
secondary controller. Changing this secondary controller to
“Primary (Active)” state resets this controller and the primary
controller. In addition, resetting the controller causes the system
to temporarily loose the link. Reads and writes occurring when the
administrator resets this controller back to “Primary (Active)” state
result in errors because the drives appear to have been removed.
TMS does not recommended configuring an active secondary
controller as primary unless no transmissions are taking place.
RamSan-300/320 User’s Manual - 75 -