Quorum disk

A quorum disk is an MDisk or a managed drive that contains a reserved area that is used exclusively for system management.

A system uses a quorum disk for two purposes:
  • To break a tie when a SAN fault occurs, when exactly half of the nodes that were previously a member of the system are present.
  • To hold a copy of important system configuration data. Just over 256 MB is reserved for this purpose on each quorum disk candidate.