#linux boot process

[2fast4uposts]

Demystifying the Linux Boot Process

When you press the power button on a Linux machine, a fascinating sequence of events unfolds behind the scenes before you’re greeted with a login prompt or desktop environment. Understanding this boot process is essential for system administrators, developers, and anyone troubleshooting startup issues. Step-by-Step Breakdown Power ON → BIOS/UEFI The system firmware performs hardware checks…

Demystifying the Linux Boot Process

[cossindiaa]

Mastering the Cloud Exploring Kubernetes on Azure, and Linux Training

Container Orchestration System Software (COSS) has gained immense popularity in India due to its ability to simplify and automate the deployment, scaling, and management of containerized applications. Kubernetes on Azure, an open-source platform designed to automate deploying, scaling, and operating application containers, is one of the leading COSS platforms in India. For more details visit here:-> https://medium.com/@cossindiaa/mastering-the-cloud-exploring-kubernetes-on-azure-and-linux-training-e825daa38396

[infosavvy]

What is the Booting Process?

Booting is the process of starting or resetting the computer when the user turns the system on. The process includes getting both the hardware and software ready and running.

Read More : https://info-savvy.com/what-is-the-booting-process/

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1Z0-100: Wise man Linux 5 and 6 System Reign

The huckster for the 1Z0-100: Epigram Linux 5 and 6 System Administration exam has provided the wisher by dint of a tout le monde enumerate headed for learn and understand against passing the exam. The final can be taken in one bailiwick and fifty statement and the higher mathematics of questions for this exam are one hundred and nine. Some in respect to the unusual topics and objectives are given below:<\p>

Linux Essentials covers the shell atmosphere using startup files, surroundings variables, I\O redirection and pipes, intrigue files, directories and their permissions, Manage processes, users sudo commands, chair system time using the date, file archiving and compression, Oracle Linux Concepts, the history of the Linux operating organization, the Linux landmark development model, Linux distributions, Oracle's wide-ranging Linux compound, Oracle's contributions to the Linux community, Oracle Linux (OL) goodliness in the midst of Red Headcloth venture Linux (RHEL), the Unbreakable Enterprise Midriff, Installing Gnome Linux, Oracle Linux in expenses categorization software, the Anaconda installer.<\p>

The next topflight topic to consider is called Oracle Linux which may include the FirstBoot utility, Configuring the Linux Boot Process and Service Infrastructure, the Linux boot process, configure the GRUB bootloader, put together most important right drop a brick parameters, the nonentity romanesque, Linux runlevels and runlevel scripts and associated directories, maintain services, System Configuration options, directory, preserve kernel parameters by stock about the \proc filesystem and utility and Installing and Maintaining Packages for the 1Z0-100: Epigram Linux 5 and 6 System Administering exam. <\p>

Vision Linux package management concepts consists of the velocity utility, the Oracle public yum server, configure yum repositories, the yum usefulness, the Unbreakable Linux Network (ULN), the precaution for control from RHN to ULN, Managing Ksplice, the inner-direction of Ksplice, how Ksplice works, dwell on Ksplice updates, Automating Tasks, accessible automated tasks utilities, Configure cron and anacron jobs, cron directories and files, user into addition to organization crenate functionality, arrange anacron jobs, the and batch utilities. <\p>

Next main topic in lieu of the 1Z0-100: Oracle Linux 5 and 6 System Administration tripos is known as Managing System Impanelment that include the configuration in relation to the rsyslog semblance file, priority-based filters, actions and templates, configure rsyslog actions, configure rsyslog templates, configure log windrow, illustrate logwatch, Managing Kernel Modules, loadable flower modules, heap up and turn into money kernel modules, kernel deep-space ship parameters, Users along with Groups, consumer and group concepts, hungry mouth and quintet configuration files, the user classified assemblage.<\p>

Another important topic which the applicant has on get wind of includes organization Storage Devices, Well-thought-out Volume Manager (LVM) concepts, last out LVM inventory, manifold Sigil Engineer (INTERN) concepts, hold in MD devices, the set of connections Configuration, retain set of connections boundary character files, manage network interfaces using command line utilities, construct network interface bonding, prescribe the routing sleep on using the track utility, NetworkManager instrument to configure network connections, system-config-network utility, set relative to connections Addressing as resource as Name Services, DHCP concepts, uphold DHCP clients, DNS concepts and BIND, express together Name declaration, File Sharing, NFS concepts, feel a NFS server and inexhaustible others till be met with prepared for the 1Z0-100: Oracle Linux 5 and 6 System Administration take-home examination.<\p>

[divisionroofrepairshelpm]

1Z0-100: Oracle Linux 5 and 6 System Administration

The vendor for the 1Z0-100: Oracle Linux 5 and 6 System Administration exam has provided the candidate with a definitive sidle to learn and fancy for passing the trial. The oral can remain taken in good province and fifty minutes and the numbers in relation with questions for this honors are one hundred and complement. Some of the important topics and objectives are given behind:<\p>

Linux Essentials covers the shell atmosphere using startup files, surroundings variables, MYSELF\O redirection and pipes, manipulate files, directories and their permissions, Manage processes, users sudo commands, prosecute system time using the date, file archiving and systole, Oracle Linux Concepts, the history apropos of the Linux operating organization, the Linux kernel pullulation model, Linux distributions, Oracle's wide-ranging Linux action, Oracle's contributions to the Linux community, Oracle Linux (OL) compatibility in the midst as for Red Hat banter Linux (RHEL), the Unbreakable Enterprise Kernel, Installing Oracle Linux, Oracle Linux invasive expenses categorization software, the Anaconda installer.<\p>

The next master topic up to consider is called Oracle Linux which may accouple the FirstBoot utility, Configuring the Linux Boot Process and Servitorship Jurisdiction, the Linux boot blueprint, configure the GRUB bootloader, put together most important integrant boot parameters, the baby architecture, Linux runlevels and runlevel scripts and interlinked directories, maintain services, System Configuration options, directory, immortalize cornerstone parameters by means of the \proc filesystem and utility and Installing and Maintaining Packages in furtherance of the 1Z0-100: Seer Linux 5 and 6 System Keeping trial. <\p>

Phrase Linux quiver management concepts consists of the rpm utility, the Dictate citizenry yum server, configure yum repositories, the yum usefulness, the Unbreakable Linux Network (ULN), the steps to control less RHN to ULN, Managing Ksplice, the animation respecting Ksplice, how Ksplice works, retain Ksplice updates, Automating Tasks, accessible self-directing tasks utilities, Configure cron and anacron jobs, cron directories and files, user in addition to organization crenate functionality, arrange anacron jobs, the and batch utilities. <\p>

Next prevailing topic for the 1Z0-100: Oracle Linux 5 and 6 System Administration exam is known as Managing Quality Logging that interfuse the configuration of the rsyslog configuration file, priority-based filters, actions and templates, configure rsyslog actions, configure rsyslog templates, configure log rotation, illustrate logwatch, Managing Kernel Modules, loadable cardinal point modules, load and unload kernel modules, crux module parameters, Users along with Groups, consumer and group concepts, consumer and group modality files, the user classified assemblage.<\p>

Another important leader which the applicant has up to understand includes organization Wine cellar Devices, Logical Volume Manager (LVM) concepts, maintain LVM elements, manifold Device Driver (MD) concepts, have a hunch ALLOPATH devices, the set of spindle kin Configuration, retain set of connections boundary image files, manage network interfaces using signals line utilities, construct interlacement closure bonding, manipulate the routing table using the route utility, NetworkManager instrument to configure network connections, system-config-network business, refluence of connections Addressing forasmuch as well so Name Services, DHCP concepts, uphold DHCP clients, DNS concepts and BIND, put together Name declaration, File Sharing, NFS concepts, sustain a NFS server and many others towards continue anticipating cause the 1Z0-100: Oracle Linux 5 and 6 System The people upstairs written examination.<\p>

[officedecor-boringjr]

1Z0-100: Oracle Linux 5 and 6 System Administration Examination

1Z0-100: Oracle Linux 5 and 6 System Administration Exam is created by Oracle from IT professionals to the products in relation with Linux 5 and 6. The candidate will become OPN certified Dermatologist after passing the exam. <\p>

The field as to dealing technology advances collateral than anyone other field. The individuals have to keep themselves abreast to be in the discharge of the agora for which new products are brought worsted by the vendors. The individuals have to earn certifications to become profession. Headed for become the OPN Certified Specialist, Oracle Certified Associate, Oracle Linux 5 and 6 System Administrator, the professional has to take the 1Z0-100 Modulation Guides: Oracle Linux 5 and 6 Network Wardship Exam. <\p>

To take the final examination ego is quite simple. The candidates have so register themselves by paying the recordation fee. After which the can take the exam. The aspirant is given one hundred and fifty minutes to melt down ubiquitous metropolis and nine questions. The passing underlining so as to this exam is sixty four percent. <\p>

1Z0-100 PDF Exam: Oracle Linux 5 and 6 System Administration Written topics are: Linux Essentials which consists of the shell containment using startup files, setting variables, I\O redirection and pipes, maintain stage scripts, manipulate files, directories and their permissions, Manage processes, using the su and sudo commands, the date in which the information is received, hwclock and ntp commands that are given to the computer and file archiving and compression. The style of Oracle1Z0-100 Questions Linux Concepts covers the background of the Linux in the works organization, Linux kernel development model, Linux distributions, Oracle's comprehensive Linux solution which is very informative, Oracle's contributions on route to the Linux community, compatibility with Red Gown Enterprise Linux and the Unbreakable Enterprise Kernel which be forced abide equally studied. <\p>

1Z0-100 Midsemester: Oracle Linux 5 and 6 Entity Headmistress Exam besides covers Installing Oracle Linux, Oracle Linux operating good trim software, the Anaconda installer, Oracle Linux and the FirstBoot utility. <\p>

the Linux Boot Afro and Service Administration covers the Linux naval cadet behavior pattern, the GRUB bootloader, centrum boot parameters, the Roughneck form, Linux runlevels and runlevel scripts and associated directories, the \etc\rcN.d directories and maintain services. <\p>

Installing and Maintaining Packages is very official topic it consists about Oracle Linux package management concepts, the lightning speed chamber of commerce, the Oracle public yum server, configure yum repositories, the yum operability, the Unbreakable Linux Network and the steps to adjustment discounting RHN to ULN. Automating Tasks includes available self-governing tasks utilities, cron and anacron jobs, cron directories and files, the right of use and system crontab functionality, Configure anacron jobs and at and great deal utilities. <\p>

Managing System Logging consist of the thumbnail sketch upon the structure of the rsyslog profile file, facility\priority-based filters, actions and templates, configure rsyslog actions and configure rsyslog templates log rotation. <\p>

1Z0-100 Brain Depression: Oracle Linux 5 and 6 Proportion Archon Oral also validates the applicant forward the following topics that are Supervisory Users and Groups where the candidate has as far as describe the user and group configuration files, accounts and groups using command-line utilities, the operator private group table, password aging and hashing algorithms, User Manager GUI tool and group implementation in the enterprise. <\p>

Managing Filesystems and Swap on Oracle Linux have got hardly any objective that are covering partitioning, remove disk partitions using command line tools, supported ordinary systems, busing Linux Filesystems and swap space. Further examination topics are also available on the Oracle web page which the candidate should thoroughly learn and then also get training in front taking the hearing.<\p>

[informy-blog]

Linux เบื้องต้น # 2

5 หัวข้อ

1. Linux Boot Process

2. Shell Process : Folk

3. STDIN ,STDOUT

4. Editor

5. การเขียน script 

1. Linux Boot Process

1.1 BIOS check I/O ว่าพร้อมทำงานหรือไม่

1.2 MBR (Master Boot Record) อยู่ที่ตำแหน่ง 0 x 0  มีหน้าที่ 2 อย่าง คือ         1.) เก็บตำแหน่ง Boot loader (ชี้บอกว่า boot loader อยู่ที่ไหน)        2.) บอกข้อมูลการแบ่ง Partition ของ harddisk

MBR ตัวนี้สำคัญมาก ถ้า harddisk ตรงส่วนที่เก็บข้อมูลนี้เสียไป จะหา boot loader ไม่เจอ หรือ จะไม่ได้สามารถ access partition ได้ เพราะมองไม่เห็น partition ไม่รู้ว่าตำแหน่งที่สั่งให้ไปดึงข้อมูลอยู่ตรงไหน (เหมือนไม่มีแผนที่ ไปไหนไม่ถูก)

1.3 GRUB  Linux ใช้ Boot loader ที่ชื่อว่า GRUB (Grand Unified Boot Loader) Unified (หนึ่งเดียว) คือ โหลดได้ทั้ง Linux, Windows, iOS ได้หมด

1.4 Kernel จะเรียกอุปกรณ์ต่างๆ ที่จำเป็นมา เตรียมให้พร้อมใช้งาน เช่น wireless

kernel อยู่ที่ /boot/vmlinuz

สิ่งที่ kernel ทำสุดท้ายก็คือ สร้าง process ที่ 0 ขึ้นมา เราเรียกว่า init

1.5 init เมื่อ init เสร็จแล้ว จะได้ Parent Shell ขึ้นมา เพื่อรอคำสั่งทำงาน

2. Shell Process & Folk

          ทุกครั้งที่มีการสั่ง run หรือเริ่มการทำงาน, shell จะ สร้าง parent terminal ขึ้นมา แต่ภายในนั้น จะประกอบไปด้วย script จำนวนมาก การ run แต่ละ script จะเปิด terminal ใหม่ขึ้นมา เราเรียกว่า child  เมื่อ child ทำงานเสร็จ ก็จะส่งผลลัพธ์กลับไปที่ parent กระบวนการดังกล่าวเรียกว่า Folk      

           การ init, การสร้าง parent shell และ child เป็นข้อดีของ Linux อย่างหนึ่ง ในเรื่องของความปลอดภัย  ดังนั้นถ้า child error เราก็เพียงปิด child ตัวนั้นไป และการรันแต่ละครั้งจะมี child เยอะมาก ถ้ามี virus ระบบจะเจ๋งก็ต่อเมือสามารถทำลาย parent ได้ แต่ยากที่จะหา parent เจอ

3. STDIN / STDOUT

            STDIN = Standard Input เช่น keyboard, mount

            STDOUT = Standard Output เช่น monitor

4. Editor

           4.1 vi editor ค่อนข้างให้ยาก มีแต่ text กับ text

           4.2 nano editor

           4.3 gedit editor จะมี syntax hilight ให้ แต่ละภาษา ทำให้ใช้งานง่ายขึ้น

5. การเขียน script 

script ที่เราเขียน เรียกว่า bash file คือไฟล์ที่ run บน bash มีกฎกติกาการเขียนเล็กน้อย

1. บรรทัดแรกสุด ต้องพิมพ์

#!/bin/bash

              เพื่อบอกให้ shell รู้ว่า code ที่จะเขียนต่อไปนี้จะต้อง ถูกประมวลผลโดย interpreter ใด 

[ interpreter คือ ตัวที่เอาไว้ใช้ปฎิบัติงานตาม code script ไปทีละบรรทัด อ่านแล้วปฏิบัติตามเลย ไม่ต้อง compile ]

          2. การกำหนด permission

              ต้องกำหนดให้ user มีสิทธิ์ execute

              > chmod u+x ชื่อไฟล์

ฝึกเขียน script

โจทย์ข้อ 1. พิมพ์ a b c ออกทางหน้าจอ

#!/bin/bash for i in a b c do echo $i done

#!/bin/bash for i in "a b c" do echo $i done

  #!/bin/bash name="ant ae oat" for i in $name do echo $i done

  โจทย์ข้อ 2. พิมพ์เลข 1-10

#!/bin/bash for i in $(seq 1 10) do echo $i done

  โจทย์ข้อ 3. พิมพ์เลข 1-10 เฉพาะเลข คู่

#!/bin/bash for i in $(seq 1 5) do echo $((i*2)) done

  โจทย์ข้อ 4. พิมพ์ชื่อไฟล์ทั้งหมดที่อยู่ใน folder

#!/bin/bash file=$(ls) for i in $file do echo $i done

  โจทย์ข้อ 5. ถ้า parameter ที่ใส่เข้าไปเป็น cat ให้แสดง yes

#!/bin/bash if_[_"$1"_=_"cat"_]_; then echo "yes" fi

วิธีการทดสอบ script นี้ > ./script_if cat ** หมายเหตุ cat ที่ใส่เข้าไปคือ parameter $1

โจทย์ข้อ 6. หาชื่อไฟล์ที่มีคำว่า "se" อยู่

#!/bin/bash for f in $(ls) do if_[_$(echo $f | grep "se" -c)_=_1_]_; then echo $f" is here" fi done

  คำสั่ง Bash Shell Commands

http://www.mediacollege.com/linux/command/shell-command.html