cmSysSecondaryPII is a read-only Permanent Interface Identifier identifying the SCM board currently serving as the standby controller in a redundant system. Administrators check it to verify a backup controller is actually present and assigned before relying on cmSysRedundancy to protect against a primary SCM failure. For instance, if this object returns no valid PII, it signals the system currently has no working secondary and a primary SCM failure would take the whole chassis down.