Lock_Timeout=seconds

    Determines the maximum time the backup operation will wait for
    the quiet-point lock and any other locks needed during online
    backup operations. When you specify the Lock_Timeout=seconds
    qualifier, you must specify the number of seconds to wait for the
    quiet-point lock. If the time limit expires, an error is signaled
    and the backup operation fails.

    When the Lock_Timeout=seconds qualifier is not specified, the
    backup operation will wait indefinitely for the quiet-point lock
    and any other locks needed during an online backup operation.

    The Lock_Timeout=seconds qualifier is ignored for offline backup
    operations.