Home PC Games Linux Windows Database Network Programming Server Mobile  
           
  Home \ Linux \ Examples of RAID levels and achieve Operational Details     - HDFS Hadoop Distributed File System Works (Server)

- Ubuntu is not in the sudoers file problem solving (Linux)

- CentOS ClamAV antivirus package updates (Linux)

- Android Unzip the ZIP / GZIP data (based on the InflaterInputStream implementation) (Programming)

- How to Install Redis server on CentOS 7 (Server)

- Interesting example of Linux Sort command (Linux)

- Tmux Crash Course: Tips and adjustment (Linux)

- Java garbage collection and heap memory layout (Programming)

- Python Django model within the class meta Detailed (Programming)

- Spring loaded container finishes executing a method (Programming)

- Use install_updates upgrade GAMIT / GLOBK (Linux)

- Linux non-root user uses less than 1024 ports (Linux)

- Getting Started with Linux system to learn: how to install the Shrew Soft IPsec VPN on Linux (Linux)

- To install the Oracle 10.2.0.1.0 process notes on Oracle Linux 4u4 (Database)

- Linux basic introductory tutorial ---- Software Installation under Linux (Linux)

- Linux /var/spool/ insufficient clientmqueue space solutions (Linux)

- Linux FAQ - How to fix tar:Exitingwith failure status due to previous errors (Linux)

- Red Hat Linux mount U disk (Linux)

- Qt for file splitting and fusion gadgets (Programming)

- Httpclient4.4 of principle (Http execution context) (Programming)

 
         
  Examples of RAID levels and achieve Operational Details
     
  Add Date : 2018-11-21      
         
         
         
  One, RAID Brief History

1.RAID Origin

Berkeley: Berkeley proposed: A case for Redundent Arrays of Inexpensive Disks as RAID (Redundant Array of Inexpensive)

Today: Redundant Arrays of Independent Disks Redundant Array of Independent

2. The advantages and expressions

1) through parallel disk read and write, the ability to improve IO:

2) by disk redundancy (fault tolerance) mechanisms to achieve greater durability:

3. Level: multiple disks organizations work together differently

RAID0, RAID1, RAID2, RAID3, RAID4, RAID5, RAID6, RAID7, RAID10, RAID01, RAID50, JBOD

4. implementation

(1) software simulation to achieve: Software RAID, combine kernel md (multi devices) Tools

Production environment generally are not in use

(2) hardware: hardware-level RAID configurations across multiple disks to achieve in the bios

External disk arrays: providing adaptation capacities through an expansion card

Inscribed formula RAID: motherboard integrated RAID controller

1) can be extended through the SAS interface, serial port adapter interface attached storage to logical unit number LUN performance

Narrowband: 8 interfaces, 7target

Broadband: 16 interfaces, 15 target

2) RAID controller requires drivers to use the system, the BIOS can be set to connect to the RAID via adapter

3) RAID controller itself a CPU, a memory can also be accelerated, another way to set the power off when the emergency is written

Two, RAID level and mode of operation

Common level: RAID-0, RAID-1, RAID-5, RAID-10, RAID-50, JBOD

1.RAID-0: 0, striped volume, strip;

Performance: read, write performance; no fault tolerance

Space used: N * min (S1, S2, ...),

Requires a minimum number of disk: at least two

Bands: the smallest capacity disk will block the production of disk-based strip

2.RAID-1: 1, mirrored, mirror;

Performance: read performance, write performance declined slightly; with redundant capability

Space used: 1 * min (S1, S2, ...), each storing the same content

Space utilization: 1/2

Requires a minimum number of hard drives: at least two

3.RAID-4: a single disk as a central parity disk

Independent access mode, the strip from the RAID3 of small data blocks to larger blocks of data

Check more quickly, but the write speed is poor, more complex controller design

XOR by one of the drives, centralized storage checksum

Allows a hard disk is damaged, but because the focus check cause performance bottlenecks

4.RAID-5: cyclic check storage mechanism

Performance: read and write performance, fault tolerance: a disk

Use of space: (N-1) * min (S1, S2, ...) short-board effect

Space utilization: (n-1) / n

Minimum Disks: at least three, may downgrade


5.RAID-6: cyclic check storage mechanism, a hard disk specialize parity disk, check code stored twice

Performance: read, write performance; fault tolerance: 2 Disk

Space used: (N-2) * min (S1, S2, ...)

Minimum Number of disks: at least four

6.RAID-7: Business

The new RAID standard, a separate "computer storage", with its own real-time operating systems and intelligent storage management software tool is used, you can run completely independent of the host, do not take up host CPU resources

7.RAID-10: do first mirror, then a strip

Performance: reading, writing and promotion, there is redundancy

Space utilization: 1/2

Minimum Number of disks: At least 4

8.RAID-01: do first bands to do the mirror

Performance: reading, writing and promotion, there is redundancy

Space utilization: 1/2

Minimum Number of disks: At least 4

9.RAID-50:

Performance: reading and writing promotion; redundant capability

Space utilization: (n-2) / n

Minimum Number of disks: At least 6

10.JBOD: Just a Bunch Of Disks multiple disk space will incorporate a large continuous space usage

Performance: no lift; no redundancy

Use of space: the size of the disk and the sum (S1, S2, ...)

Space utilization: 100%

Minimum Number of disks: At least 2

Three, RAID kernel implements observations related commands

Achieve CentOS 6 on software RAID

1.md (multi devices) tools, mdadm: modular tools

The syntax of the command: mdadm [mode] [options]

Supported RAID levels: LINEAR linear fashion, RAID0, RAID1, RAID4, RAID5, RAID6, RAID10;

Mode: Create: -C; assembly: -A; Monitoring: -F; management: -f, -r, -a

: / dev / md #

: any block device

(1) -C: Create Mode

-n #: # use a block device to create this RAID;

-l #: RAID level specified to be created;

-a {yes | no}: Target RAID device to automatically create a device file;

-c CHUNK_SIZE: specified block size; the default 512k

-x #: specify the number of idle disks;

(2) management:

-f: Specifies the disk marked as damaged;

-a: Adding a Disk

-r: Remove Disk

(3) -D: show detailed information of the raid; mdadm -D / dev / md #

(4) observation md state: cat / proc / mdstat

(5) Stop md devices: mdadm -S / dev / md #

2.watch: dynamic observation command during operation

Format: watch -n # 'COMMAND'

-n #: refresh interval in seconds;
     
         
         
         
  More:      
 
- iostat command Detailed (Linux)
- Linux beginners to develop the seven habits (Linux)
- Linux system started to learn: Teaches you install Ubuntu 15.04 on VirtualBox (Linux)
- CentOS set up FTP server (Server)
- Bash variable expansion modifier (Programming)
- Use the Find command to help you find those files that need to be cleaned (Linux)
- MongoDB common optimization settings in Linux (Database)
- Ubuntu configuration SVN and http mode access (Server)
- Single Instance ASM under CRS-4124, CRS-4000 error handling (Database)
- Under Ubuntu 15.04 installation JDK8 (Linux)
- Java Access Control (Programming)
- Linux system - The understanding cpu load (Linux)
- Linux the best download manager uGet (Linux)
- Ubuntu Eclipse configuration Gtk + 2.0 libraries (Linux)
- Oracle 12c R2 new feature dbca command to create a standby database (Database)
- Spark SQL job of a lifetime (Server)
- Eclipse 3.7.2 can not start solving under Ubuntu 14.04 (Linux)
- Ubuntu 14.04 installed Nvidia CUDA 7.5 and build Python Theano deep learning development environment (Linux)
- C # and JavaScript arrays to re-summary (Programming)
- How Linux Log Analysis (Linux)
     
           
     
  CopyRight 2002-2022 newfreesoft.com, All Rights Reserved.