the host environment
DESCRIPTION
The Host Environment. Module 2.1. The Host Environment. Upon completion of this module, you will be able to: List the hardware and software components of the host environment Describe key protocols and concepts used by each component. Examples of Hosts. Server. Laptop. Group of Servers. - PowerPoint PPT PresentationTRANSCRIPT
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The Host Environment The Host Environment
Module 2.1
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The Host Environment
Upon completion of this module, you will be able to:
List the hardware and software components of the host environment
Describe key protocols and concepts used by each component
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Examples of Hosts
Laptop
Server
Group of Servers
Mainframe
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Host Physical Components
Bus
I/O Devices
CPU Storage
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CPU
CPU
Bus
BusALU
Registers
L1 Cache
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Storage
…
0
1
2
3
n
Data 0
Data n
Data 2
Data 3
Data 1
Address Content
Disk
Memory
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Storage Hierarchy – Speed and Cost
Speed
Slow
Fast
CostHighLow
TapeOptical
disk
Magnetic disk
RAM
L2 cache L1 cache
CPU registers
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I/O Devices
Human interface– Keyboard
– Mouse
– Monitor
Computer-computer interface– Network Interface Card (NIC)
Computer-peripheral interface– USB (Universal Serial Bus) port
– Host Bus Adapter (HBA)
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Host Environment: Logical Components
Host
Apps
Volume Management
DBMS Mgmt Utilities
File System
Multi-pathing Software
Device Drivers
HBA HBA HBA
Operating System
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Host
Apps
Volume Management
DBMS Mgmt Utilities
File System
Multi-pathing Software
Device Drivers
HBA HBA HBA
Operating System
File Systems
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File System: Metadata Examples
UNIX (UFS)
File type and permissions
Number of links
Owner and group IDs
Number of bytes in the file
Last file access
Last file modification
Windows (NTFS)
Time stamp and link count
File name
Access rights
File data
Index information
Volume information
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File Systems: Journaling and Logging
Improves data integrity and system restart time over non-journaling file systems.
Uses a separate area called a log or journal.– May hold all data to be written
– May hold only metadata
Disadvantage - slower than other file systems.– Each file system update requires at least 1 extra write – to the
log
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Volume Management
Host
Apps
Volume Management
DBMS Mgmt Utilities
File System
Multi-pathing Software
Device Drivers
HBA HBA HBA
Operating System
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HBAsHost
Apps
Volume Management
DBMS Mgmt Utilities
File System
Multi-pathing Software
Device Drivers
HBA HBA HBA
Operating System
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Improving Data Availability at the Host
Redundancy:
Multiple HBAs
Multi-pathing software
Clustering
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How Files are Moved to and from Storage
Teacher
Configures / Manages
File System Files
Mapped by file system
to
Course File(s)
Reside in
File System Blocks
Disk Physical Extents
Consisting of
LVM Logical Extents
Residing in
Mapped by LVM to
Disk Sectors
Managed by Disk Storage Subsystem
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Module Summary
Key points covered in this module:
Hosts typically have:– Hardware: CPU, memory, buses, disks, ports, and interfaces.
– Software: applications, operating systems, file systems, device drivers, volume managers
HBAs connect hosts to storage devices.
Multi-pathing software uses redundant paths to ensure uninterrupted communication between the host and the storage
Clustering uses redundant host systems to improve data availability
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Check Your Knowledge
What are some examples of hosts?
Describe the hardware components found in most hosts.
What is the function of the operating system?
What is the function of the file system?
What are some techniques that can be used to improve availability at the host?
What is volume management?