Exploring Storage Technologies: From Evolution to Performance

This document discusses storage devices and technologies. It covers hard drives, solid state drives (SSDs), magnetic hard drive geometry, and SSD technologies. The key topics covered are the components and operation of mechanical hard drives, including platters, read/write heads, and cylinders/tracks/sectors; the advantages of SSDs over hard drives in terms of reliability and performance; and technologies used in SSDs like NAND flash memory, write amplification, and wear leveling. The document also lists the CompTIA exam objectives covered in this chapter on storage devices.

1. Exploring Storage Technologies: From Evolution to Performance A Comprehensive Journey Through the World of Data Storage

2. Table of contents Overview of Storage Topics Evolution of Data Storage Memory Storage Devices Advancements in Hard Disks LTO Tape Cartridges Storage Building Blocks Disk Drive Types Disk Drive Command Sets Understanding SSD Disks Disk Capacity Growth Trends Importance of Kryder's Law Tape Libraries and VTLs Controllers in Storage Systems 01 02 03 04 05 06 07 08 09 10 11 12 13

3. Table of contents RAID Configurations Overview RAID 0 and RAID 1 Explained RAID 1 and RAID 10 Configurations RAID 10 vs. RAID 5 Performance Understanding RAID 6 Technology Data Deduplication in Storage Cloning and Snapshotting Services Snapshots vs. Clones Thin Provisioning in Storage DAS vs. SAN Systems Fibre Channel Technology Fibre Channel over Ethernet (FCoE) FCoE vs. iSCSI Technologies 14 15 16 17 18 19 20 21 22 23 24 25 26

4. Table of contents SAN vs. NAS Systems Clustered NAS and Object Storage Object Storage and SDS Storage Performance Considerations 27 28 29 30

5. Overview of Storage Topics Importance of Caching in Disk Systems Enhances performance by reducing access time Minimizes latency and improves I/O operations Storage Tiering Creates a hierarchy based on cost and performance Optimizes resource allocation and management Introduction to Information Lifecycle Management (ILM) Manages data based on value and policies Ensures data is stored in the most appropriate tier 1 Exploring Storage Technologies: From Evolution to Performance Use of Automated Tiering Optimizes storage efficiency Reduces manual intervention and errors Challenges of Managing Multiple Storage Tiers Complexity in categorizing data Difficulty in ensuring optimal placement

6. Evolution of Data Storage Early Storage Methods Punched cards and paper tape were used as basic persistent storage systems in early computers. Drum Memory Introduced in the 1950s, drum memory was one of the first magnetic read/write storage systems widely used. Mainframe to PCs Transition from mainframes to PCs brought about various file formats like BMP, GIF, MP3, and MPEG. Importance of Open Standards Storing data in structured, human-readable formats like XML text files ensures long-term readability. Storage Media Evolution From floppy disks to CDs to Blu-ray, data transfer to the latest storage media standard every 10 years is recommended for longevity. 2 Exploring Storage Technologies: From Evolution to Performance

7. Memory Storage Devices Memory Storage Devices Memory storage devices play a crucial role in storing and accessing data efficiently. Different types of memory storage devices include RAM (Random Access Memory) and ROM (Read-Only Memory). RAM is volatile memory used for temporary data storage, providing fast access for running applications. ROM is non-volatile memory that stores firmware and essential system instructions. Flash memory, commonly found in USB drives and SSDs, offers a balance between speed and non-volatility. 3 Exploring Storage Technologies: From Evolution to Performance

8. Advancements in Hard Disks Increased Rotation Speeds Hard disks have evolved to have faster rotation speeds, allowing for quicker data access and improved performance. Enhanced Seek Times Advancements in hard disk technology have led to reduced seek times, enabling faster data retrieval. Improved Interface Protocols Modern hard disks utilize advanced interface protocols for efficient data transfer and communication with other system components. 4 Exploring Storage Technologies: From Evolution to Performance Enhanced Reliability Advancements in hard disk design have improved reliability, reducing the risk of data loss and system failures. Higher Capacities Hard disks now offer significantly larger storage capacities, allowing for the storage of vast amounts of data in a single drive.

9. LTO Tape Cartridges LTO Tape Cartridges LTO tape cartridges have a market share of over 80%. The latest LTO-7 tape cartridges can store up to 6 TB of uncompressed data. Typical tape throughput ranges from 100 to 150 MB/s. Existing tape drives typically use 4 Gbit/s Fibre Channel interfaces, supporting a sustained throughput of between 350 and 400 MB/s. LTO-5 drives require an 8 Gbit/s FC interface to support up to 800 MB/s. 5 Exploring Storage Technologies: From Evolution to Performance

10. Server Storage Options Servers can utilize internal storage or external storage, often combined with internal storage. Types of Disks Disks are crucial storage building blocks, with two main types in use today: mechanical hard disks and SSD disks. Disk Controllers These disks are connected to disk controllers using a command set based on ATA or SCSI. Storage Building Blocks 6 Exploring Storage Technologies: From Evolution to Performance

11. Disk Drive Types SATA Disks Low-cost, high-capacity disks ideal for bulk storage applications. Commonly used in PCs, laptops, and for archiving or backup due to their cost-effectiveness. Controlled using the SMART command set for disk management. SAS Disks High-end disks with faster rotational speeds (10,000 or 15,000 rpm) compared to SATA disks. Better error correction capabilities and reliability than SATA disks. Utilize the SCSI command set for error-recovery and reporting. NL-SAS Disks Combine SAS interface with SATA disk mechanics. Used for bulk storage applications due to their cost-effectiveness and energy efficiency. Spin at 7,200 rpm and can be combined with faster SAS disks in storage arrays. Solid State Drives (SSDs) Based on flash technology with no moving parts for high performance. Offer faster data access compared to mechanical disks (microseconds vs. milliseconds). All-flash arrays using SSD disks preferred for high-demanding OLTP systems. 7 Exploring Storage Technologies: From Evolution to Performance

12. Disk Drive Command Sets Disk Drive Connections Disk drives are connected to disk controllers using command sets based on ATA or SCSI. SATA Disks SATA disks use the SMART command set for disk control. The SMART command set is limited but easy to implement. SAS Disks SAS disks utilize the SCSI command set. SCSI provides better error correction capabilities compared to SATA disks. 8 Exploring Storage Technologies: From Evolution to Performance SSD Disks SSD disks are based on flash technology. They are connected using a standard SAS disk interface. They provide high performance due to their lack of moving parts. NL-SAS Disks NL-SAS disks combine the SAS interface with the mechanics of SATA disks. They offer a balance between speed and cost.

13. SSD disks, or Solid State Drives, are storage devices that do not have moving parts. They are based on flash technology, which is semiconductor-based memory. SSDs offer high performance due to their lack of moving parts, allowing for faster data access compared to traditional mechanical disks. These drives are commonly connected using a standard SAS disk interface. Most storage vendors now offer all-flash arrays, which are storage systems using only SSD disks for enhanced performance. SSD Disks Understanding SSD Disks 9 Exploring Storage Technologies: From Evolution to Performance

14. Disk Capacity Growth Trends Disk Capacity Growth Trends Disk capacity has shown exponential growth over the years, following Kryder's Law. In the 1960s, a core memory of 8 bytes has evolved into an 8 GB micro SD flash card, showcasing a billion-fold increase in storage capacity. The trend of increasing disk capacity continues to shape the storage landscape, enabling more data to be stored efficiently. This growth in disk capacity has revolutionized data storage capabilities, allowing for the storage of vast amounts of information in compact formats. Understanding the historical context of disk capacity growth provides insights into the rapid advancements in storage technologies. 10 Exploring Storage Technologies: From Evolution to Performance

15. Importance of Kryder's Law Kryder's Law and Storage Capacity Growth Kryder's Law illustrates the remarkable growth in storage capacity over the years. Significant increase in the amount of data that can be stored. Designing Efficient Storage Infrastructure Understanding Kryder's Law is crucial for designing storage infrastructure efficiently. Highlights the need to adapt to advancements in technology by implementing new disks just in time. Optimizing Storage Systems By aligning storage expansion with Kryder's Law, organizations can optimize their storage systems. Handle increasing data demands effectively. Scalable and Cost-Effective Storage Solutions Implementing storage solutions in line with Kryder's Law ensures scalability. Storage infrastructure remains cost-effective in the face of rapid data growth. 11 Exploring Storage Technologies: From Evolution to Performance

16. Tape Libraries Tape Libraries, like the one depicted in Picture 24, can store a significant number of tapes, such as 150 LTO tapes with a total capacity of 750 TB. Virtual Tape Libraries (VTLs) Virtual Tape Libraries (VTLs) utilize disks for storing backups and emulate traditional tape devices and formats for seamless integration with backup applications. VTL solutions commonly employ NL-SAS or SATA disk arrays for cost-effectiveness and efficiency in handling multiple virtual tape drives in parallel. Data stored on VTL disk arrays can be exported to other media, like physical tapes, for disaster recovery purposes. VTLs offer high-performance disk-based backup and restore capabilities, ensuring data protection and availability in critical scenarios. Tape Libraries and VTLs 12 Exploring Storage Technologies: From Evolution to Performance

17. Controllers connect disks and tapes to servers, providing high performance and availability using RAID technology. They are crucial in NAS or SAN deployments, linking disks and tapes to redundant Fibre Channel, iSCSI, or FCoE connections. Controllers implement features like cloning, data deduplication, and thin provisioning to optimize storage efficiency. By virtualizing physical disks into Logical Unit Numbers (LUNs), controllers enable seamless interaction with the operating system without revealing the underlying disk details. Controllers in Storage Systems Controllers in Storage Systems 13 Exploring Storage Technologies: From Evolution to Performance

18. RAID Configurations Overview RAID Solutions RAID (Redundant Array of Independent Disks) solutions provide high availability and performance through redundant disks. Common RAID Levels Commonly implemented RAID levels include RAID 0 (Striping), RAID 1 (Mirroring), RAID 10 (Striping and Mirroring), RAID 5 (Striping with distributed parity), and RAID 6 (Striping with distributed double parity). RAID 1 RAID 1 involves disk mirroring for high availability, with mirror disks often placed in separate enclosures for optimal redundancy. 14 Exploring Storage Technologies: From Evolution to Performance Importance of RAID RAID configurations play a crucial role in optimizing data distribution and reliability within storage systems. RAID 10 RAID 10 combines striping and mirroring, offering both high performance and availability at a higher cost.

19. RAID 0 and RAID 1 Explained RAID 0: Striping Enhances performance by spreading data across multiple disks. Cost-effective and boosts read and write speeds by accessing data from multiple disks simultaneously. Lacks data redundancy, meaning if one disk fails, all data is lost. RAID 1: Mirroring Ensures high availability by duplicating data on two disks. Data is written to both disks simultaneously, providing reliability in case of disk failure. Considered the most reliable RAID level but comes at a higher cost due to data redundancy. 15 Exploring Storage Technologies: From Evolution to Performance

20. RAID 1 and RAID 10 Configurations RAID 1 Overview RAID 1 involves mirroring data on two disks for high availability and data protection. RAID 1 is considered the most reliable RAID level but comes at a higher cost due to the redundancy of data on two disks. Optimizing RAID 1 To optimize high availability in RAID 1, it is recommended to place mirror disks in a separate enclosure and use redundant disk controllers. RAID 10 Overview RAID 10 combines striping and mirroring for high performance and availability, but at a relatively high price. RAID 10 requires at least four disks, with only 50% of the disk space being used for data storage, while the rest is used for mirroring. 16 Exploring Storage Technologies: From Evolution to Performance

21. RAID 10 vs. RAID 5 Performance RAID 10 Combines striping and mirroring for high performance and availability. Requires at least four disks, utilizing 50% of disk space for mirroring. Provides faster write operations compared to RAID 5 due to its mirroring setup. RAID 5 Offers a balance between performance and data protection with distributed parity. Has a higher penalty for write operations due to its parity calculations. 17 Exploring Storage Technologies: From Evolution to Performance

22. Understanding RAID 6 Technology RAID 6 Overview RAID 6 is a storage technology that offers a high level of data protection through its use of distributed double parity. Data Striping and Dual Parity In RAID 6, data is striped across multiple disks like in RAID 5, but with the added feature of dual parity for enhanced fault tolerance. Fault Tolerance This dual parity allows RAID 6 to withstand the simultaneous failure of up to two disk drives without losing any data. 18 Exploring Storage Technologies: From Evolution to Performance Performance Trade-off While RAID 6 offers robust data protection, it comes with a trade-off of slightly reduced write performance due to the additional parity calculations required. Suitability RAID 6 is particularly suitable for environments where data integrity and fault tolerance are critical, providing an extra layer of protection compared to RAID 5.

23. Data deduplication in storage is a process where duplicate data is identified and replaced with pointers to existing data to save disk space. This process can be executed during low-performance periods to minimize the impact on system performance. All-flash storage systems are ideal for efficient deduplication due to their fast read and write speeds. Deduplication enables all-flash systems to host fewer disks compared to traditional storage systems, offsetting the higher cost of SSD disks. Data Deduplication in Storage Data Deduplication in Storage 19 Exploring Storage Technologies: From Evolution to Performance

24. Cloning and Snapshotting Services Cloning and Snapshotting Services in Enterprise Storage Systems Cloning and snapshotting services are essential features provided by enterprise storage systems. Cloning involves creating a full copy of a disk, allowing for independent use of the copied data. Snapshotting captures a specific point in time of the data on disks, preventing further writes to those disks during the snapshot period. These services are valuable for creating backups, test data sets, and reverting to older data without the need to restore from a backup. 20 Exploring Storage Technologies: From Evolution to Performance

25. Snapshots and clones are essential services provided by enterprise storage systems. Cloning involves creating a full copy of a disk, similar to a RAID 1 mirror disk. Snapshotting captures a specific point in time of the data on disks, preventing writing to those disks during the snapshot period. Both cloning and snapshotting are useful for creating backups and test sets of data. Cloning allows for creating backups without affecting the original disks that are still online. Snapshots and Clones Snapshots vs. Clones 21 Exploring Storage Technologies: From Evolution to Performance

26. Thin Provisioning in Storage Thin Provisioning in Storage Allows for allocating more storage capacity to users than physically installed. Operates similarly to overcommitting memory in virtual machines, optimizing storage usage. Traditional Storage Applications Provided with predetermined physical storage space, often leading to underutilization. Monitoring and Allocation Thin provisioning closely monitors actual storage needs and adds physical disk space only when necessary. Cost Optimization Defers disk purchases until truly needed, optimizing storage capacity and costs. 22 Exploring Storage Technologies: From Evolution to Performance

27. Direct Attached Storage (DAS) DAS is a storage system where dedicated disks connect to a controller via SAS or SATA protocols, providing disk blocks to the computer for file storage. DAS is commonly used for boot devices and caching in servers, offering storage that is only available to the server with the DAS storage attached. Storage Area Network (SAN) SAN is a specialized storage network that connects servers to disk controllers using technologies like Fibre Channel or iSCSI. SAN offers virtual disks to servers in the form of LUNs (Logical Unit Numbers), which are only accessible to the server with that specific LUN mounted. The core of a SAN is a set of SAN switches known as the Fabric, enabling the connection of multiple servers to a large pool of central storage. DAS vs. SAN Systems 23 Exploring Storage Technologies: From Evolution to Performance

28. Fibre Channel is a high-speed network technology primarily used for storage area networks (SANs). It provides reliable and fast data transfer rates, ranging from 1 to 128 Gbit/s. Fibre Channel operates over fiber optic cables, ensuring secure and efficient data transmission. This technology is known for its low latency and high bandwidth capabilities, making it ideal for demanding storage environments. Fibre Channel supports features like zoning and masking to enhance security and manage access to storage resources. Fibre Channel Technology Fibre Channel Technology 24 Exploring Storage Technologies: From Evolution to Performance

29. Fibre Channel over Ethernet (FCoE) Fibre Channel over Ethernet (FCoE) FCoE is a switching technology that does not involve routing and requires specialized switches. It is typically implemented gradually, starting with the host and switch layers, while back-end storage arrays continue to run native Fibre Channel. FCoE enables the convergence of Fibre Channel storage traffic onto Ethernet networks. Specialized FCoE enabled switches are necessary due to the requirement of DCB or CEE Ethernet. FCoE implementation allows for the coexistence of Fibre Channel and Ethernet in the same network infrastructure. 25 Exploring Storage Technologies: From Evolution to Performance

30. FCoE vs. iSCSI Technologies FCoE (Fibre Channel over Ethernet) FCoE is a switching technology that does not involve routing and requires specialized switches. Typically implemented gradually, starting with the host and switch layers, while back-end storage arrays continue to run native Fibre Channel. iSCSI (Internet Small Computer System Interface) Allows the SCSI protocol to run over Ethernet LANs using TCP/IP. Provides a cost-effective alternative to Fibre Channel and is gaining popularity in the SAN market with advancements in Ethernet speeds. Comparison of FCoE and iSCSI Both offer unique advantages and considerations in storage networking technologies. 26 Exploring Storage Technologies: From Evolution to Performance

31. SAN (Storage Area Network) operates by offering disk blocks that are exclusive to a single server. NAS (Network Attached Storage) provides a shared filesystem accessible by multiple servers. SAN uses technologies like iSCSI, Fibre Channel, or FCoE for communication, while NAS uses SMB/CIFS or NFS over TCP/IP. NAS systems typically offer redundancy, load balancing, data replication, and other services, freeing up operating systems from these tasks. NAS has knowledge about the files it stores, enabling optimized file handling and file-level services like snapshot and clone technology. SAN vs NAS SAN vs. NAS Systems 27 Exploring Storage Technologies: From Evolution to Performance

32. Clustered NAS Utilizes a distributed file system across multiple servers to provide unified access to files. Object Storage Manages data as objects with unique identifiers and metadata, accessed through a REST API over HTTP. Simplifies data location and enables massive scalability, suitable for static data like backups and archives. High availability is achieved through replication across multiple servers and locations. Clustered NAS and Object Storage 28 Exploring Storage Technologies: From Evolution to Performance

33. Object Storage and SDS Object Storage Object Storage manages data as objects with unique identifiers and metadata. Object Storage uses a REST API over HTTP for data retrieval and storage. Software-Defined Storage (SDS) SDS virtualizes physical storage into a shared storage pool. SDS provides data services like deduplication, compression, and tiering. APIs are used to provision storage pools and set performance levels in SDS. 29 Exploring Storage Technologies: From Evolution to Performance

34. Disk Performance Variation Differences in disk rotation speed, seek times, and interface protocol impact overall performance. High-end disks with faster rotation speeds can handle more operations per second efficiently. Importance of Caching Systems Storage vendors implement caching to significantly boost performance by buffering data for reads and writes. Read-cache acts as a buffer for repeated reads, enhancing data retrieval speed. Types of Disk Drives SATA disks are cost-effective and suitable for bulk storage applications. SAS disks are high-end with better error correction capabilities. NL-SAS disks combine SAS interface with SATA mechanics for bulk storage. SSDs, based on flash technology, offer high performance due to their lack of moving parts. Storage Performance Considerations 30 Exploring Storage Technologies: From Evolution to Performance