If the interchange was fault-driven, there are two ways of finding the cause.

• Using alarm and error logs in conjunction with the timestamp described below.

  After a spontaneous server interchange has occurred, the alarm log retains a record of any MAJOR ON-BOARD alarm against a server component that took place before the interchange. This record is retained for 3 hours and may indicate the cause of the interchange when testing is not possible or conclusive. Other information in the error log may also be helpful.