| 摘要 |
Server supervisor processes in the segment nodes of a database cluster afford transparent reset mechanisms to a fault tolerant service (FTS). FTS probes only primary segments as to their status unless a primary segment does not respond, in which case FTS will probe the mirror of that primary-mirror pair, and change the state of the mirror to primary if the primary is faulty. Only a primary segment to initiate a reset of its mirror segment and then resets itself. If a mirror segment fails, it shuts down and its corresponding primary segment will report the failure to FTS. Transient communication failures are addressed by retry logic on FTS probing, and not reported to FTS. Reset is not initiated by FTS and preserves the segment state in the absence of errors. |
