Linux first week Summary
In this week I made a gradually enter the IT industry outsider to the industry, from the basic structure and principles of computers and servers, how to set up the system operation and maintenance environment, which summarize the knowledge learned this week.
The first is the operation and maintenance personnel of the three responsibilities:
1. To ensure that data is not lost
2. To ensure stable operation of the service,
3. To ensure user access experience
A server hardware detail
1. Server hardware - Power
(1) Provide redundancy
(2) providing a multiple power
(3) providing uninterruptible power supply UPS
(4) provide a generator
2. The server hardware -CPU
(1) .CPU large ones described
(2) .CPU described Audit
3. The server hardware - Memory
(1) The program concept note
(2). Process Concept Note (Daemon)
(3) .buffer cache buffer cache concept differs
4. The server hardware - Disk
(1) The disk interface type
The disk array card Introductory description
(1) can obtain a higher capacity
(2) Higher performance may be obtained
(3) You can get more security
And conversion data storage unit 6. Description
Memory unit: 1024Byte (bytes) == 1KB
1024KB == 1MB
1024MB == 1GB
1024GB == 1TB
1024TB == 1PB
1024PB == 1EB
1024EB == 1ZB
7. The server hardware - Remote
(1) Using the Remote Management Card for remote management
(2) The remote switch
(3) Remote Production raid
(4) Remote mounting system
(5) The main independence and integration into independent NIC
(6) remote management cards from different vendors Category Description
dell - idrac
HP - ilo
IBM - RSA
(7) The array card
The main role of the array cards is integrated into multiple logical hard disk of a hard disk, the hard disk can enhance the performance, safety, capacity, common array card raid0, raid1, raid5, raid10.
raid0
raid0 the multiple drives, all of the hard work equally stored, along with data storage, no data redundancy.
Advantages: high efficiency, a hard disk may be 100% utilization
Disadvantages: low security, any damage to the hard disk data will be lost, can not be recovered
RAID1
raid1 by the two hard disks, the same data is simultaneously written to two hard disk, it writes data redundancy by copying, a hard disk may be broken by another drive recovery.
Advantages: safe
Disadvantages: low efficiency, 50% utilization rate may be hard
raid5
raid5 of at least three hard disks, write a piece of data will be written check code section, data recovery can be done when a hard disk via parity data loss.
Advantages: high efficiency, high security
Disadvantages: bad two or more hard disk data can not be recovered, the available capacity of the hard disk (n-1) / n, n is the number of hard disk
raid 10
raid10 raid1 mode is simply composed of two raid0 to simultaneously improve performance and safety
Advantages: high efficiency, high security
Disadvantages: hard disk usage by 50%, a very low price (for a lot of hard to construct)
(8) The array card performance comparison
Efficiency: raid0> raid10> raid5> raid1
Security: raid1> raid10> raid5> raid0
Cost-effective: raid0> raid5> raid1> raid10
8. Remote Management Card
Remote management card is similar to our usual PC Remote Assistance feature, but he can control the server in the server off, power on the server, and then operate.
9. The server hardware - CD-ROM
(1) it is mainly used for installation of the system (to be phased out)
10. The server hardware - Cabinets
(1) The cabinet wiring DESCRIPTION Introduction
11. The server hardware performance comparison
CPU> Memory> SSD Solid State Disk> normal hard disk
II. How to store data in the enterprise
1. Large Enterprise: Concurrent higher than
→ stored user data is written into memory (buffer) - time quantitative (settings) stored in the hard disk →
Reading user data read ← ← hard to read (hotspot data) from the memory (buffer)
2. SMEs: concurrency is lower than
→ save user data is written to memory (buffer) - Real-time write (soon) stored in the hard disk →
Reading user data read ← ← hard to read (hotspot data) from the memory (buffer)
III. Operating System
The role of the operating system is to use hardware and software management, software every step of the operation to be scheduled by the operating system to hardware, and returns the results to the software.
Kernel: control hardware, machine language (binary)
Interpreter: bash interpreter
Peripheral software programs: C language java pyhon etc.
Four, Linux systems Introduction and Installation
1.Linux time of birth
In 1969 Bell Labs Unix systems the birth of the late fees
In 1983 Stallman launched the free software movement, founded FSF Free Software Foundation, the GNU project open: goals made and Unix as good, but the open source system
Results: development kernel (failure), the development of the interpreter (success), software development (success)
1984 University professor (Tan Bangning) Minux system for teaching birth
In 1991 Linus Torvalds Linux kernel born free and open source
In 1994 Linux 1.0 came, he unified the GNU / Minix / Unix
(1) .redhat Internet field - server, foreign / state-owned enterprises, the application process fee, has its own trademark logo;
(2) .centos: Internet field - server, private, free, not Red Hat;
(3) .Ubuntu: home terminal computer, the graphical interface;
(4) .Debian / FreeBSD: System Security requirements are relatively high, security and stable high, mainly used in finance, games;
(5) .SUSE: there is a need to network services company, to act as a network device, mail server, Germany;
(6) .Fredora: testing, development of new software programs for testing.
Red Hat - New Fredora beta -> Test redhat - release the official version of redhat
Red Hat - New Fredora beta -> Test (7) .centos - centos release the official version
2.Linux system environment deployment and installation
(1) Computer hardware environment
at least
CPU Intel i5
8G memory
500G hard drive
(3) The virtualization environment
Windows X64 VMware 12/15
x86 32-bit support for up to 4GB of memory
x64 64 location theory supports 128G of memory
(4) Download the system image
Linux system image can be downloaded in many places, such as the official website, Ali cloud and so on, we have an example here to CentOS
CentOS versions
CentOS -7 - x86_64 -DVD - 1810.iso
CentOS7.6 Standard image file
CentOS -7 - x86_64 -Everything - 1810.iso
CentOS7.6 full version of the image file
CentOS -7 - x86_64 -LiveGNOME - 1810.iso
CentOS7.6 show version of the image file
CentOS -7 - x86_64 -LiveKDE - 1810.iso
CentOS7.6 show version of the image file
CentOS -7 - x86_64 -Minimal - 1810.iso
CentOS7.6 Lite image file
CentOS -7 - x86_64 -NetInstall - 1810.iso
CentOS7.6 network installation version of the image file
(5) Load Mirroring
(6) Start Hosting
When you start a virtual host, if an error occurs, look at the computer supports virtualization, if supported, went to open the BIOS virtualization, the specific operation on their own Baidu.
Virtual machine configuration
(7) Install Linux
Countdown interface card configuration information name
After tab Input: net.ifnames = 0 biosdevname = 0
system configuration information
Network configuration information
Operating system partition
/ Boot boot boot partition and save the relevant data
200M
swap swap hard disk space will act as a temporary memory usage (to prevent out of memory down machine)
Memory <8G swap = 1.5 * Memory Memory size> = 8G swap = 8G
/ Root partition all remaining partition to the root partition
software settings
CentOS7 configuration selection 1236
CentOS6 configuration options 235
Finally, set about password can reboot the
Then after a successful startup to enter a user name root, and then enter the password set before you can operate. (Note: The password input process is not visible, no asterisk)