DOCSLIB.ORG

Disk Drive Diagnostics Profile

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Disk Drive Diagnostics Profile 1 2 Document Number: DSP1113 3 Date: 2014-05-22 4 Version: 1.1.0a 5 Disk Drive Diagnostics Profile Information for Work-in-Progress version: IMPORTANT: This document is not a standard. It does not necessarily reflect the views of the DMTF or all of its members. Because this document is a Work in Progress, it may still change, perhaps profoundly. This document is available for public review and comment until the stated expiration date. It expires on: <2014-07-31> Provide any comments through the DMTF Feedback Portal: http://www.dmtf.org/standards/feedback 6 Document Type: Specification 7 Document Status: Work In Progress 8 Document Language: en-US Disk Drive Diagnostics Profile DSP1113 9 Copyright notice 10 Copyright © 2014 Distributed Management Task Force, Inc. (DMTF). All rights reserved. 11 DMTF is a not-for-profit association of industry members dedicated to promoting enterprise and systems 12 management and interoperability. Members and non-members may reproduce DMTF specifications and 13 documents, provided that correct attribution is given. As DMTF specifications may be revised from time to 14 time, the particular version and release date should always be noted. 15 Implementation of certain elements of this standard or proposed standard may be subject to third party 16 patent rights, including provisional patent rights (herein "patent rights"). DMTF makes no representations 17 to users of the standard as to the existence of such rights, and is not responsible to recognize, disclose, 18 or identify any or all such third party patent right, owners or claimants, nor for any incomplete or 19 inaccurate identification or disclosure of such rights, owners or claimants. DMTF shall have no liability to 20 any party, in any manner or circumstance, under any legal theory whatsoever, for failure to recognize, 21 disclose, or identify any such third party patent rights, or for such party’s reliance on the standard or 22 incorporation thereof in its product, protocols or testing procedures. DMTF shall have no liability to any 23 party implementing such standard, whether such implementation is foreseeable or not, nor to any patent 24 owner or claimant, and shall have no liability or responsibility for costs or losses incurred if a standard is 25 withdrawn or modified after publication, and shall be indemnified and held harmless by any party 26 implementing the standard from any and all claims of infringement by a patent owner for such 27 implementations. 28 For information about patents held by third-parties which have notified the DMTF that, in their opinion, 29 such patent may relate to or impact implementations of DMTF standards, visit 30 http://www.dmtf.org/about/policies/disclosures.php. 2 Work in Progress - Not a DMTF Standard Version 1.1.0a DSP1113 Disk Drive Diagnostics Profile 31 CONTENTS 32 Foreword ....................................................................................................................................................... 6 33 Introduction.................................................................................................................................................... 7 34 Document conventions .......................................................................................................................... 7 35 Typographical conventions ......................................................................................................... 7 36 ABNF usage conventions ........................................................................................................... 7 37 1 Scope .................................................................................................................................................... 9 38 2 Normative references ............................................................................................................................ 9 39 3 Terms and definitions .......................................................................................................................... 10 40 4 Symbols and abbreviated terms .......................................................................................................... 10 41 5 Synopsis .............................................................................................................................................. 12 42 6 Description .......................................................................................................................................... 13 43 7 Implementation .................................................................................................................................... 14 44 7.1 Disk drive test information ........................................................................................................ 14 45 7.2 CIM_DiskDriveDiagnosticTest .................................................................................................. 17 46 7.3 CIM_DiskDriveDiagnosticSettingData ...................................................................................... 19 47 7.3.1 CIM_DiskDriveDiagnosticSettingData.LBAStart .......................................................... 20 48 7.3.2 CIM_DiskDriveDiagnosticSettingData.LBAEnd ........................................................... 20 49 7.3.3 CIM_DiskDriveDiagnosticSettingData.Seed ................................................................ 20 50 7.3.4 CIM_DiskDriveDiagnosticSettingData.DataSizes ........................................................ 20 51 7.3.5 CIM_DiskDriveDiagnosticSettingData.DataPatterns ................................................... 20 52 7.4 CIM_DiskDriveDiagnosticServiceCapabilities .......................................................................... 21 53 7.4.1 CIM_DiskDriveDiagnosticServiceCapabilities.Region ................................................. 21 54 7.4.2 CIM_DiskDriveDiagnosticServiceCapabilities.Seed .................................................... 22 55 7.4.3 CIM_DiskDriveDiagnosticServiceCapabilities.DataSizes ............................................ 22 56 7.4.4 CIM_DiskDriveDiagnosticServiceCapabilities.DataPatterns ....................................... 22 57 7.5 Disk Drive Diagnostics Profile indications support ................................................................... 22 58 7.5.1 CIM_IndicationFilter (StaticIndicationFilter) ................................................................. 22 59 7.5.2 CIM_FilterCollection (ProfileSpecificFilterCollection) .................................................. 23 60 7.5.3 CIM_MemberOfCollection (IndicationFilterInFilterCollection) ..................................... 23 61 7.5.4 CIM_OwningCollectionElement (IndicationServiceOfFilterCollection) ........................ 23 62 7.6 Diagnostics alert indications and standard messages .............................................................. 23 63 7.6.1 DIAG501 - The selected disk drive is not present. ...................................................... 23 64 7.6.2 DIAG502 - The selected disk drive is offline. ............................................................... 24 65 7.6.3 DIAG503 - The selected disk drive is disabled by the user. ........................................ 24 66 7.6.4 DIAG512 - Disk drive in error ....................................................................................... 25 67 7.6.5 DIAG513 - The disk drive has an unrecognized state ................................................. 25 68 7.6.6 DIAG514 - The disk drive is in a predictive failure state .............................................. 26 69 7.6.7 DIAG515 - The disk drive is in a predictive failure state for unknown reason ............. 27 70 7.6.8 DIAG516 – Drive has an interface CRC error ............................................................. 27 71 7.6.9 DIAG517 – Drive has a media error ............................................................................ 28 72 7.6.10 DIAG518 – Data contains an uncorrectable error ....................................................... 28 73 7.6.11 DIAG551 – Test aborted due an invalid DiagnosticSettings value .............................. 29 74 7.6.12 DIAG51 – Test aborted due an invalid DiagnosticSettings value ................................ 29 75 7.6.13 Disk drive alerts using common messages ................................................................. 30 76 8 Methods ............................................................................................................................................... 32 77 8.1 CIM_DiagnosticTest.RunDiagnosticService( ) ......................................................................... 32 78 8.1.1 CIM_DiskDriveDiagnosticTest ..................................................................................... 32 79 8.1.2 CIM_DiskDriveDiagnosticSettingData ......................................................................... 32 80 8.1.3 CIM_DiskDriveDiagnosticServiceCapabilities ............................................................. 32 81 8.2 Profile conventions for operations ............................................................................................ 32 82 9 Use cases ............................................................................................................................................ 32 Version 1.1.0a Work in Progress - Not a DMTF Standard 3 Disk Drive Diagnostics Profile DSP1113 83 9.1 Use case summary ..................................................................................................................
Load more

Recommended publications
  • Problem 1 : Write-Based Skippy. Problem 2 : Skippy Variant
    CMU 18-746 Storage Systems Assigned: 1 Feb 2010 Spring 2010 Homework 2 Due: 22 Feb 2010 Solutions are due at the beginning of class on the due date and must be typed and neatly organized. Late homeworks will not be accepted. You are permitted to discuss these problems with your classmates; how- ever, your work and answers must be your own. All questions should be directed to the teaching assistant. Problem 1 : Write-based Skippy. Before answering the following two problems, please read the following paper: Microbenchmark-based Extraction of Local and Global Disk Characteristics by Nisha Talagala, Remzi H. Arpaci-Dusseau, and David Patterson (Berkeley TR CSD-99-1063). It is available from the course website. (a) First, describe in words the functionality of lseek. Specifically, what happens when lseek(fd, 1048576, SEEK CUR) is issued? (b) Refer to Figure 1, which shows the result of simulating the Skippy experiment on a disk simulator. Label this graph with the following values: rotational latency, MTM, sectors per track, number of heads, head switch time, and cylinder switch time. Also label the head and cylinder switches. Make sure you mark the parts of the figure that indicate these values. (c) How would Figure 1 change, if the disk were replaced with one that has a higher rotation speed, but is the same in every other respect? (d) If the WRITEs used in the Skippy experiment were replaced with READs, do you think the observed value for MTM would change? Explain your answer. Problem 2 : Skippy variant. Assume the skippy algorithm is replaced with the following: fd = open ( ‘ ‘ raw d i s k d e v i c e ’ ’ ) ; ¡ f o r ( i = 0 ; i measurements ; i + + ) l s e e k ( fd , 0 , SEEK SET ) ; w r i t e ( fd , b u f f e r , SINGLE SECTOR ) ; / / time t h e f o l l o w i n g w r i t e and o u t p u t i , time ¢ / / i i s t h e hop s i z e l s e e k ( fd , i £ SINGLE SECTOR , SEEK SET ) ; w r i t e ( fd , b u f f e r , SINGLE SECTOR ) ; ¤ c l o s e ( fd ) ; Figure 2 shows the results of running this experiment (it is a plot of time vs.
    [Show full text]
  • Lecture 7 Slides
    ✬ ✩ Computer Science CSCI 251 Systems and Networks Dr. Peter Walsh Department of Computer Science Vancouver Island University [email protected] ✫ 1: Computer Science CSCI 251 — Lecture 7 ✪ ✬ ✩ Virtualization Process • CPU virtualization Address Space • memory virtualization File • persistent storage virtualization ✫ 2: Computer Science CSCI 251 — Lecture 7 ✪ ✬ ✩ Formatting Low Level • sector creation • sector addressing using LBA (Logical Block Addressing) e.g., (cylinder 0, head 0, sector 1) = LBA 0, (cylinder 0, head 0, sector 2) = LBA 1 etc. • usually completed at time of manufacture Partitioning • each physical disk can be divided into partitions • a partition is a logical disk under OS control High Level • typically involves file system creation ✫ 3: Computer Science CSCI 251 — Lecture 7 ✪ ✬ ✩ IBM PC Basic I/O System (BIOS) BIOS • firmware executes on power-on startup • assumes disk data structure and boot-loader code starting at LBA 0 of bootable disk Legacy BIOS • LBA 0 contains MBR (Master Boot Record) • MBR contains the partition table • a partition entry contains a 32 bit start LBA field UEFI (Unified Extensible Firmware Interface) • GPT (GUID Partition Table) starts at LBA 0 • GPT contains the partition table • a partition entry contains a 64 bit start LBA field ✫ 4: Computer Science CSCI 251 — Lecture 7 ✪ ✬ ✩ IBM PC Basic I/O System (BIOS) cont. 3ΤΙςΕΞΜΡΚ7]ΩΞΙΘ &−37 9)∗− 4ΕςΞΜΞΜΣΡ 1&6 +48 4ΕςΞΜΞΜΣΡ 8ΕΦΠΙ 8ΕΦΠΙ &ΣΣΞ &ΣΣΞ 0ΣΕΗΙς 0ΣΕΗΙς −&14∋,ΕςΗ[ΕςΙ ✫ 5: Computer Science CSCI 251 — Lecture 7 ✪ ✬ ✩ IDE Devices Controller • typically can support 4 drives (2 ports) Old Naming Convention Device Name Port# Drive# /dev/hda 1 1 /dev/hdb 1 2 /dev/hdc 2 3 /dev/hdd 2 4 New Naming Convention Device Name Port# Drive# /dev/sda 1 1 /dev/sdb 1 2 /dev/sdc 2 3 /dev/sdd 2 4 ✫ 6: Computer Science CSCI 251 — Lecture 7 ✪ ✬ ✩ SATA Devices Controller • typically can support 2 - 6 drives (2 - 6 ports) Naming Convention Device Name Port# Drive# /dev/sda 1 1 /dev/sdb 2 2 .......
    [Show full text]
  • My Name Is Muhammad Sadiq, I Hope You Are Also Fine. Complete Current Soled Paper CS609
    Hi! My name is Muhammad Sadiq, I hope you are also fine. Complete current soled paper CS609. Just remember in prayer. And visit my site you’ll a lot of information. http://tipshippo.com/ Thanks! QNO1: calculate the sector#for the followinsg cluster 1CH We have following information Block per cluster = 8 First user block number = 20 Ans: No. of System Area Blocks = Reserved Block + Sector per FAT * No. of FAT’s + No. of entries * 32 / Bytes per Block First User Block No. = No. of System Area Blocks Sector No. = (Clust_no – 2)* Blocks per Clust + First User Block # QNO2: which control information PSP ( program segment prefix) contains Ans: It contains control information like DTA (Disk Transfer Area) and command line parameters. QNO3: IN case of memory to memory transfer which MDA register is used to simulate DMA request. Ans: DMA request register can be used to simulate a DMA request through software (in case of memory to memory transfer). The lower 2 bits contains the channel number to be requested and the bit # 2 is set to indicate a request. can be used to simulate a DMA request through software (in case of memory to memory transfer). The lower 2 bits contains the channel number to be requested and the bit # 2 is set to indicate a request. QNO4: what are the effects of surface area on disk size. Ans: Increasing the surface area clearly increases the amount of data that can reside on the disk as more magnetic media no resides on disk but it might have some drawbacks like increased seek time in case only one disk platter is being used QNO5:how can we read / write the disk block when LSN is given.
    [Show full text]
  • RDX Performance
    WHITE PAPER RDX Performance This whitepaper is intended to address performance issues related to installation and usage of RDX® removable storage systems. Performance related topics discussed in this whitepaper include: • Host system performance considerations. An overview of performance impacts of host system configuration, including hardware and software configuration. • Performance benchmarks. Industry standard benchmarks used to validate system and RDX performance • RDX Cartridge performance considerations. An overview of the RDX Cartridge and an understanding of performance related aspects. • RDX interconnect performance considerations. An overview of interconnect related issues (USB/SATA) and possible performance impacts. A typical installation of the RDX SATA or USB drive should automatically achieve desired performance. The purpose of this whitepaper is to introduce performance related concepts and provide a troubleshooting means in the unlikely event that performance related issues arise. Performance Overview Transfer rates for SATA and USB RDX drives are shown in the table below. Transfer rates of competing Travan and DAT72 tape technologies are shown for reference. TRANSFER ratE BY PRODUCT RDX SATA RDX USB DAT72 Travan TR-7 Native Transfer Rate (MB/s) 30 25 3.51 1.22 Time to complete 20GB 0.19 0.22 1.59 4.63 Data Transfer (hours) Transfer Rate by Product Time to complete 20Gb Data Transfer 35 30 Travan TR-7 25 DAT72 20 MB/s 15 RDX USB 10 5 RDX SATA 0 RDX SATA RDX USB DAT72 Travan TR-7 0 1 2 3 4 5 Figure 1: Transfer Rate Compression www.tandbergdata.com WHITE PAPER Guide to Data Protection Best Practices A second transfer rate, “up to 45MB/s,” in some literature when referencing the RDX drive.
    [Show full text]
  • Understanding and Installing Hard Drives ‐ Chapter #8
    Understanding and Installing Hard Drives ‐ Chapter #8 Amy Hissom Key Terms 80 conductor IDE cable — An IDE cable that has 40 pins but uses 80 wires, 40 of which are ground wires designed to reduce crosstalk on the cable. The cable is used by ATA/66, ATA/100, and ATA/133 IDE drives. active partition — The primary partition on the hard drive that boots the OS. Windows NT/2000/XP calls the active partition the system partition. ANSI (American National Standards Institute) — A nonprofit organization dedicated to creating trade and communications standards. autodetection — A feature on newer system BIOS and hard drives that automatically identifies and configures a new drive in the CMOS setup. block mode — A method of data transfer between hard drive and memory that allows multiple data transfers on a single software interrupt. boot sector virus — An infectious program that can replace the boot program with a modified, infected version of the boot command utilities, often causing boot and data retrieval problems. CHS (cylinder, head, sector) mode — The traditional method by which BIOS reads from and writes to hard drives by addressing the correct cylinder, head, and sector. Also called normal mode. DMA transfer mode — A transfer mode used by devices, including the hard drive, to transfer data to memory without involving the CPU. ECHS (extended CHS) mode — See large mode. EIDE (Enhanced IDE) — A standard for managing the interface between secondary storage devices and a computer system. A system can support up to six serial ATA and parallel ATA IDE devices or up to four parallel ATA IDE devices such as hard drives, CD-ROM drives, and Zip drives.
    [Show full text]
  • Heading 1 Example
    Hard Disk Drive Long Data Sector White Paper Authors: P. Chicoine, Phoenix; M. Hassner, Hitachi GST; E. Grochowski, Consultant; S. Jenness, Microsoft; M. Noblitt, Seagate; G. Silvus, Broadcom; C. Stevens, Western Digital; B. Weber, LSI Corporation April 20, 2007 Abstract This paper summarizes the results of the IDEMA Long Data Sector (LDS) Committee that was started in 2000. The activities of this committee were motivated by a 1998 NSIC Paper, in which the incompatibility of HDD Industry areal density growth at the existing 512-Byte Sector Format and maintaining data integrity was recognized. Contents 1. Motivation, Scope and History …………………………………………..………………………………….1 2. Impact on OS/Software Applications ………………………………….………………………………. 2 3. Storage Systems Support Required for LDS ……………………….……………………………… 5 4. Large Block Error Correction ………………………………………………………………………………….6 5. Summary ……………………………………………………………………………………………………………….9 6. References …………………………………………………………………………………………………………….10 6.1. Windows Vista Support for LDS 6.2. HGST LDS Position Statement 6.3. Fujitsu LDS Position Statement 6.4. Seagate LDS Position Statement 6.5. Maxtor LDS Position Statement 6.6. IDEMA Letter to Microsoft 6.7. Integrated Sector Format ECC for Aligned LDS 6.8. Alignment Method for LDS 6.9. Western Digital White Paper re Implementation of Larger Sectors 1. Motivation, Scope and History The motivation behind the IDEMA LDS Committee activity lies in the realization that continued HDD areal density growth, while maintaining the data integrity required by HDD storage customers, at the current 512-byte sector format, are incompatible in the long run. As a result of this realization, Seagate, Maxtor, Hitachi GST, and Fujitsu agreed to form a committee, under IDEMA’s sponsorship, to address long data sectors.
    [Show full text]
  • 21 Disk Formatting
    Disk Formatting Low Level Formatting Preparing a disk for use Physical Formatting - Low-Level Format - Electronically lays down tracks and sectors on the platter surfaces - Places tracks and sectors on platters - Starting and ending points of all sectors are - Partition Disk marked - Identifies and marks bad sectors - Creates logical disks (volumes) - Writes physical sector addresses - Hard Disk Only - By default, formatting does not wipe disk - High-Level Format - Filling sectors with NULL character 00 is - Creates and initializes file system for option each volume - Low level formatting is performed by manufacturer - Requires special software - Requires many hours for gigabyte drives Low Level Formatting Low Level Formatting Addressing Physical Sectors Addressing Physical Sectors Physical LBA - Address written into sector during low Addressing for HD Floppy Disks Cylinder-Head-Sector (CHS) 2048 512 level formatting Cylinders Count Addresses - Sector address limited by BIOS - Must have before sector can be read Tracks/ 80 0 - 79 Head 2 8 Cylinders - Cylinders can only be numbered 0 to 1023 - If address is corrupted or missing - Heads can only be numbered 0 to 15 52 52 “Sector Not Found” error is given Heads/Sides 2 0 - 1 Sector - Sectors can only be numbered 1 to 63 Cylinder-Head-Sector (CHS) (512, 8, 52) Sectors/ 18 1 - 18 Logical Block Addressing (LBA) Controller reports - Sector address limited by BIOS Blocks CHS - (5, 1, 9) - Converts actual CHS address into a The LBA addressing scheme hides - Cylinders can only be numbered 0 to 1023 logical address acceptable to BIOS Cylinder 5 the physical details of the storage - Heads can only be numbered 0 to 15 Side 1 ('bottom') - Conversion performed by controller device from the BIOS (firmware) - Sectors can only be numbered 1 to 63 Block 9 - Formula varies by manufacturer and BIOS and operating system.
    [Show full text]
  • Datenrettung Mittels Testdisk Und Photorec / Backupkonzepte
    Datenrettung Festplattenaufbau Logischer Datentr¨ageraufbau Datentr¨ager klonen unter Linux Testdisk - Datenrettung mittels Testdisk und MBR/FS-Recovery Testdisk - Undelete Photorec - Signaturbasierte Photorec / Backupkonzepte Suche Backupkonzepte Medientypen Datentypen Backupkonzepte Christian Franzen Kontakt Chaos Computer Club Stuttgart 3. April 2009 1 / 38 Agenda Datenrettung Festplattenaufbau Logischer Datentr¨ageraufbau Datentr¨ager klonen 1 unter Linux Datenrettung Testdisk - MBR/FS-Recovery Festplattenaufbau Testdisk - Undelete Photorec - Logischer Datentr¨ageraufbau Signaturbasierte Suche Datentr¨ager klonen unter Linux Backupkonzepte Medientypen Testdisk - MBR/FS-Recovery Datentypen Backupkonzepte Testdisk - Undelete Kontakt Photorec - Signaturbasierte Suche 2 Backupkonzepte Medientypen Datentypen Backupkonzepte 2 / 38 Innenansicht Festplatte Datenrettung Festplattenaufbau Logischer Datentr¨ageraufbau Datentr¨ager klonen unter Linux Testdisk - MBR/FS-Recovery Testdisk - Undelete Photorec - Signaturbasierte Suche Backupkonzepte Medientypen Datentypen Backupkonzepte Kontakt Quelle: Wikipedia 3 / 38 Datentechnischer Aufbau Datenrettung Festplattenaufbau Logischer Datentr¨ageraufbau Datentr¨ager klonen unter Linux Testdisk - MBR/FS-Recovery Testdisk - Undelete Photorec - Signaturbasierte Suche Backupkonzepte Medientypen Datentypen Backupkonzepte Kontakt Quelle: Wikipedia 4 / 38 Begriffe Datenrettung Festplattenaufbau Logischer Datentr¨ageraufbau Datentr¨ager klonen unter Linux Fachbegriffe Testdisk - MBR/FS-Recovery Testdisk - Undelete
    [Show full text]
  • Disk Storage Disk Storage
    Disk Storage Disk Storage • Different types of disk storage: • The smallest addressable unit on a disk storage is a • Hard disks block. → Mountable disk • The size of a block is usually 512 bytes. → Non-mountable disk - Winchester disk • The storage area for a block at the disk platter is called • Floppy disks a sector. • Optical disks - CD, DVD • Old disk storage devices were addressed with cylinder number, track number, sector number. • Modern hard disks use Logical Block Addressing (LBA), that is the block address given to the controller do not tell exactly where on the platter the block is stored. • It is possible to read or write several contiguous blocks with one command. This makes it possible for the file system code to define a file system block size that is some multiple of the sector size. 1 2 Rotational speed Disk Formatting Two variants: Before a new disk can be used, information must be written to the platter that defines the tracks and sectors. This is • Constant angular velocity (CAV). The rotational called low-level formatting. speed of the disk is constant. To use the platter in an efficient way, the outer tracks have more sectors than • Low-level formatting fills the disk with a special data the inner tracks. Used in hard disks. structure for each sector. • Constant Linear velocity (CLV). The density of bits per • The data structure consists of a header, a data area track is uniform. To get constant data rate the rotation (usually 512 bytes) and a trailer. speed is increased as the head moves from the outer to • The header and trailer contain data such a sector the inner tracks.
    [Show full text]
  • Introduction: Post-Mortem Digital Forensics
    Digital Forensics 1.0.1 Introduction: Post-mortem Digital Forensics CIRCL TLP:WHITE [email protected] Edition May 2020 Thanks to: AusCERT JISC 2 of 102 Overview 1. Introduction 2. Information 3. Disk Acquisition 4. Disk Cloning / Disk Imaging 5. Disk Analysis 6. Forensics Challenges 7. Bibliography and Outlook 3 of 102 1. Introduction 4 of 102 1.1 Admin default behaviour • Get operational asap: ◦ Re-install ◦ Re-image ◦ Restore from backup ! Destroy of evidences • Analyse the system on his own: ◦ Do some investigations ◦ Run AV ◦ Apply updates ! Overwrite evidences ! Create big noise ! Negative impact on forensics 5 of 102 1.2 Preservation of evidences • Finding answers: ! System compromised ! How, when, why ! Malware/RAT involved ! Persistence mechanisms ! Lateral movement inside LAN ! Detect the root cause of the incident ! Access sensitive data ! Data exfiltration ! Illegal content ! System involved at all • Legal case: ! Collect & safe evidences ! Witness testimony for court 6 of 102 1.2 Preservation of evidences • CRC not sufficient: ◦ Example: Checksum 4711 ! 13 ◦ Example: Collision 12343 ! 13 • Cryptographic hash function: ◦ Output always same size ◦ Deterministic: if m = m ! h(m) = h(m) ◦ 1 Bit change in m ! max. change in h(m) ◦ One way function: For h(m) impossible to find m ◦ Simple collision resistance: For given h(m1) hard to find h(m2) ◦ Strong collision resistance: For any h(m1) hard to find h(m2) 7 of 102 1.3 Forensics Science • Classical forensic Locard's exchange principle https://en.wikipedia.org/wiki/Locard%27s_exchange_principle
    [Show full text]
  • Aligning Partitions to Maximize Storage Performance
    An Oracle Technical White Paper November 2012 Aligning Partitions to Maximize Storage Performance Aligning Partitions to Maximize Storage Performance Table of Contents Introduction ......................................................................................... 4 Preparing to Use a Hard Disk ............................................................. 6 How Disks Work.............................................................................. 6 Disk Addressing Methods ............................................................... 7 Hard Disk Interfaces ....................................................................... 7 Advanced Technology Attachment (ATA) ..............................................8 Serial ATA (SATA)..................................................................................8 Small Computer System Interface (SCSI) ..............................................8 Serial Attached SCSI (SAS) ...................................................................8 Fibre Channel (FC).................................................................................8 iSCSI ......................................................................................................8 Storage Natural Block Sizes ........................................................... 9 Applying Partitions to Disk Drives ..................................................... 10 Changing Standards for Partitioning ............................................. 10 How Changing Standards Affect Partition Tools and Alignment... 11 Using
    [Show full text]
  • Handling of Permanent Storage
    Operating systems (vimia219) Handling of Permanent Storage Tamás Kovácsházy, Phd 20th topic Handling of Permanent Storage Budapest University of Technology and Economics © BME-MIT 2014, All Rights Reserved Department of Measurement and Information Systems Permanent storage CPU registers Cache Physical memory Permanent storage External storage Backup storage © BME-MIT 2014, Minden jog fenntartva 2. lap Handling of the Permanent storage . Permanent storage or “storage”: o Typically compared to the physical memory o It offers orders of magnitudes bigger storage capacity o Also orders of magnitudes slower • Throughput • Latency o Nonvolatile storage • If properly used, otherwise it do losses data • Data security is a major issue! o Block based • OS handles this storage based on blocks – No byte access, a full block must be handled • A block can be read, written or erased • Programs cannot be executed directly from storage, it must be loaded into memory first! • One exception – NOR flash memory is organized as bytes (as regular memory) – It is possible to execute the OS or other programs directly from NOR flash © BME-MIT 2014, Minden jog fenntartva 3. lap How we map files to storage? . The file is the logical unit of data storage on the permanent strorage (file) o It has a name (named collection). o We reference it by its name o It’s size can vary, practically any size is allowed • There is a hard limit coming from the physical storage and the filesystem . The main task of the operating system regarding permanent storage is the mapping of files (logical unit) to blocks (physical unit) . This task is solved by the OS using a multilayer hierarchical system, solving the problem on multiple abstraction level .
    [Show full text]