Linux is a fully-featured open source operating system based on Unix. It was created by Linus Torvalds in 1991 and has since grown in popularity. Linux uses a kernel to manage hardware resources and runs on multiple hardware platforms. Users interact with Linux through a shell and can execute commands, manage files and directories, and perform other tasks. Common Linux commands include ls, cd, pwd, cp, and more.
Linux is a fully-networked, multi-user, multitasking operating system similar to Unix. It was created in 1991 by Linus Torvalds and is now used widely due to its low cost, stability, and ability to run on different hardware platforms. Linux uses a command line interface where users log in and issue commands to perform tasks like copying files, installing software, and checking system resources. Common commands include ls to list files, cd to change directories, and man to view manuals.
Linux is an open source operating system created by Linus Torvalds in 1991. It uses a Linux kernel and includes many common Unix tools. Linux is free to use and modify due to its open source licensing. It runs on many hardware platforms and is growing in popularity for servers, desktops, and embedded systems due to its low cost, stability, and security. Users can download Linux from distributions like Red Hat which package the Linux kernel with additional software and support.
Linux is an open-source operating system developed by Linus Torvalds in 1991. It has a reputation for being efficient and fast-performing. The document then lists and describes 50 common Linux commands, including their syntax and usage. Examples include commands for changing directories, copying files, displaying the date/time, searching files with grep, and more.
This document provides an overview of the Linux operating system and commands. It begins with course objectives to introduce Unix concepts, commands, and the VI editor. It then discusses what an operating system is and why they are needed before exploring the evolution, flavors, and architecture of Unix/Linux. Key topics covered include the file system structure, absolute vs relative paths, how Unix sessions work, login sequences, command syntax, and standard input/output/error. The document also examines regular expressions, shell metacharacters, editors like VI, and permissions.
The document provides summaries of common Linux commands, including their most common uses. Some key commands covered are ls, which lists files and directories; cd, which changes the current working directory; and man, which displays manuals for commands. The document also discusses commands for checking network connectivity like ping and ifconfig, managing processes like top and ps, and manipulating files and directories like touch, rm, and chmod.
Unix , Linux Commands
Unix, which is not an acronym, was developed by some of the members of the Multics team at the bell labs starting in the late 1960's by many of the same people who helped create the C programming language.
The document discusses various topics related to Linux administration. It covers Unix system architecture, the Linux command line, files and directories, running programs, wildcards, text editors, shells, command syntax, filenames, command history, paths, hidden files, home directories, making directories, copying and renaming files, and more. It provides an overview of key Linux concepts and commands for system administration.
Linux is a fully-networked, multi-user, multitasking operating system similar to Unix. It was created in 1991 by Linus Torvalds and is now used widely due to its low cost, stability, and ability to run on different hardware platforms. Linux uses a command line interface where users log in and issue commands to perform tasks like copying files, installing software, and checking system resources. Common commands include ls to list files, cd to change directories, and man to view manuals.
Linux is an open source operating system created by Linus Torvalds in 1991. It uses a Linux kernel and includes many common Unix tools. Linux is free to use and modify due to its open source licensing. It runs on many hardware platforms and is growing in popularity for servers, desktops, and embedded systems due to its low cost, stability, and security. Users can download Linux from distributions like Red Hat which package the Linux kernel with additional software and support.
Linux is an open-source operating system developed by Linus Torvalds in 1991. It has a reputation for being efficient and fast-performing. The document then lists and describes 50 common Linux commands, including their syntax and usage. Examples include commands for changing directories, copying files, displaying the date/time, searching files with grep, and more.
This document provides an overview of the Linux operating system and commands. It begins with course objectives to introduce Unix concepts, commands, and the VI editor. It then discusses what an operating system is and why they are needed before exploring the evolution, flavors, and architecture of Unix/Linux. Key topics covered include the file system structure, absolute vs relative paths, how Unix sessions work, login sequences, command syntax, and standard input/output/error. The document also examines regular expressions, shell metacharacters, editors like VI, and permissions.
The document provides summaries of common Linux commands, including their most common uses. Some key commands covered are ls, which lists files and directories; cd, which changes the current working directory; and man, which displays manuals for commands. The document also discusses commands for checking network connectivity like ping and ifconfig, managing processes like top and ps, and manipulating files and directories like touch, rm, and chmod.
Unix , Linux Commands
Unix, which is not an acronym, was developed by some of the members of the Multics team at the bell labs starting in the late 1960's by many of the same people who helped create the C programming language.
The document discusses various topics related to Linux administration. It covers Unix system architecture, the Linux command line, files and directories, running programs, wildcards, text editors, shells, command syntax, filenames, command history, paths, hidden files, home directories, making directories, copying and renaming files, and more. It provides an overview of key Linux concepts and commands for system administration.
Linux is an open-source operating system based on Unix, designed for multi-user environments. The document provides an overview of basic Linux commands like ls, mkdir, cd for navigating files and directories, as well as more advanced commands for manipulating files, checking system resources, and getting system information. It also lists and describes many common Linux commands and their functions.
The document provides an overview of basic Linux commands organized into categories such as file handling, text processing, system administration, process management, archival, network, file systems, and advanced commands. It describes the purpose and usage of common commands like ls, cd, cp, grep, kill, tar, ssh, mount, and more. It also lists resources for learning Linux commands like man pages, books, and the internet.
This document provides an overview of a 5-day UNIX/Linux training course. The training covers topics such as Linux desktops and administration, Linux command line administration, networking, servers, and programming. Each day focuses on a different aspect of UNIX/Linux including installation, desktop environments, administration tasks from the command line interface, and networking. Common Linux distributions and benefits of UNIX/Linux are also discussed.
This document describes the functions of various Linux commands, including commands for listing files (ls), creating directories (mkdir) and files (touch, cat), copying files (cp), changing directories (cd), moving files (mv), finding file locations (whereis, which), displaying manual pages (man, info), checking disk usage (df, du), viewing running processes (ps), setting aliases (alias), changing user identity (su, sudo), viewing command history (history), setting the system date and time (date), displaying calendars (cal), and clearing the terminal screen (clear). It provides the syntax and examples for using each command.
The document provides an overview of basic and useful UNIX commands organized into categories including essential commands, valuable commands, fun commands, helpful commands, and useful commands. It describes commands for navigating directories, manipulating files, editing text, sending email, connecting to other systems, monitoring system usage, and more. The document is intended to help users get started with common tasks in UNIX.
This document provides an introduction to Linux, including:
- What Linux is and where it came from, as an open source operating system created by Linus Torvalds in 1991.
- How to get Linux through downloading a distribution like Red Hat and the packages it includes.
- Why Linux has become significant due to its growing popularity, ability to run on multiple hardware platforms, and being free.
- An overview of Linux commands and utilities for file management, processes, users and permissions.
This document provides a tutorial on common Linux commands. It lists commands like ls to list files, file to check file types, mkdir to make directories, cd to change directories, cp to copy, mv to move, and rm to remove files and directories. It also covers commands like cat to view file contents, grep to search files, more and less to page through large files, chown to change ownership, chmod to change permissions, ps to view processes, and kill and killall to terminate processes. The document explains that running "man [command]" provides documentation for each command.
This document provides a summary of the Unix and GNU/Linux command line. It begins with an overview of files and file systems in Unix, including that everything is treated as a file. It then discusses command line interpreters (shells), and commands for handling files and directories like ls, cd, cp, and rm. It also covers redirecting standard input/output, pipes, and controlling processes. The document is intended as training material and provides a detailed outline of its contents.
This document provides an introduction to useful Linux commands. It begins with a brief history of UNIX and Linux and describes the Linux directory structure. It then discusses commands for navigating directories, searching for files, manipulating text, basic networking, system information, disk usage monitoring, and more. The goal is to compile some essential Linux commands for newcomers to learn and get comfortable with.
Linux is a prominent example of free and open source software. It can be installed on a wide variety of devices from embedded systems to supercomputers. Linux is commonly used for servers, with estimates that it powers around 60% of web servers. Linux distributions package the Linux kernel with other software like utilities, libraries and desktop environments. Programming languages and build tools like GCC are supported. Embedded Linux is often used in devices due to its low cost and ease of modification.
This document provides a quick guide to the Linux command line. It introduces Linux and the shell, and explains why the command line is useful even with graphical user interfaces. It then covers basic commands for file management, processes, archives, and input/output redirection. Finally, it briefly mentions some simple text editors and hints at using more advanced shell scripting.
This lecture discusses the Environment Variables concept, usage, and how processes acquire them. It then goes through the most popular ones
Check the other Lectures and courses in
http://Linux4EnbeddedSystems.com
or Follow our Facebook Group at
- Facebook: @LinuxforEmbeddedSystems
Lecturer Profile:
- https://www.linkedin.com/in/ahmedelarabawy
Online Training in Unix Linux Shell Scripting in HyderabadRavikumar Nandigam
The document provides information about the UNIX operating system. It defines UNIX as a collection of software that manages computer hardware resources and provides common services. It then discusses examples of UNIX systems like DOS, Windows, MacOS, and Linux. It covers UNIX architecture including the kernel, shell, tools, and applications. It also summarizes important UNIX commands for system information, file manipulation, permissions, and viewing files.
This document provides a tutorial on Unix/Linux. It begins with an overview of the Unix system including the kernel, shell, multi-user and multi-process capabilities, and important directory structures. It then covers basic commands, relative and absolute paths, redirecting and piping output, permissions, process management, installing software, text editors, running jobs in the foreground and background, and remote login/file transfer. The goal is to introduce fundamental Unix concepts and commands to new users.
CompTIA Linux+ Powered by LPI certifies foundational skills and knowledge of Linux. With Linux being the central operating system for much of the world’s IT infrastructure, Linux+ is an essential credential for individuals working in IT, especially those on the path of a Web and software development career. With CompTIA’s Linux+ Powered by LPI certification, you’ll acquire the fundamental skills and knowledge you need to successfully configure, manage and troubleshoot Linux systems. Recommended experience for this certification includes CompTIA A+, CompTIA Network+ and 12 months of Linux admin experience. No prerequisites required.
Useful Linux and Unix commands handbookWave Digitech
This article provides practical examples for most frequently used commands in Linux / UNIX. Helpful for Engineers and trainee engineers, Software developers. A handy notes for all Linux & Unix commands.
- Linux originated as a clone of the UNIX operating system. Key developers included Linus Torvalds and developers from the GNU project.
- Linux is open source, multi-user, and can run on a variety of hardware. It includes components like the Linux kernel, shell, terminal emulator, and desktop environments.
- The document provides information on common Linux commands, files, users/groups, permissions, and startup scripts. It describes the Linux file system and compression/archiving utilities.
This document provides an overview of a presentation on Linux programming and administration. It covers the history of Unix and Linux, files and directories in Linux, Linux installation, basic Linux commands, user and group administration, and LILO (Linux Loader). The document introduces key topics like Unix flavors, Linux distributions, partitioning and formatting disks for Linux installation, the file system hierarchy standard, and access permissions in Linux.
The document provides an overview of common Linux commands, including commands for executing other commands, navigating directories, listing and copying files, managing users and permissions, searching for files, processing text, managing archives, and compressing files. Examples are given for commands like ls, cd, cp, mv, rm, who, echo, alias, awk, chown, diff, grep, pushd, kill, df, cat, tar, gzip, su. Brief descriptions are provided for most commands and references are given at the end for additional Linux resources.
This document provides an introduction and overview of the UNIX operating system. It discusses that UNIX is an operating system, like Windows, that manages communication between software and hardware. Popular versions of UNIX include Linux and Android. The document outlines reasons for using UNIX such as reliability, low/no cost, and open source access. It describes the core components of UNIX including the kernel, bootloader, daemons, and shells. Key features like being portable, multi-user, and providing security are highlighted. Common UNIX commands and utilities are listed along with file permissions, redirection, pipes, and filters.
What is Linux?
Command-line Interface, Shell & BASH
Popular commands
File Permissions and Owners
Installing programs
Piping and Scripting
Variables
Common applications in bioinformatics
Conclusion
Linux is an open-source operating system based on Unix, designed for multi-user environments. The document provides an overview of basic Linux commands like ls, mkdir, cd for navigating files and directories, as well as more advanced commands for manipulating files, checking system resources, and getting system information. It also lists and describes many common Linux commands and their functions.
The document provides an overview of basic Linux commands organized into categories such as file handling, text processing, system administration, process management, archival, network, file systems, and advanced commands. It describes the purpose and usage of common commands like ls, cd, cp, grep, kill, tar, ssh, mount, and more. It also lists resources for learning Linux commands like man pages, books, and the internet.
This document provides an overview of a 5-day UNIX/Linux training course. The training covers topics such as Linux desktops and administration, Linux command line administration, networking, servers, and programming. Each day focuses on a different aspect of UNIX/Linux including installation, desktop environments, administration tasks from the command line interface, and networking. Common Linux distributions and benefits of UNIX/Linux are also discussed.
This document describes the functions of various Linux commands, including commands for listing files (ls), creating directories (mkdir) and files (touch, cat), copying files (cp), changing directories (cd), moving files (mv), finding file locations (whereis, which), displaying manual pages (man, info), checking disk usage (df, du), viewing running processes (ps), setting aliases (alias), changing user identity (su, sudo), viewing command history (history), setting the system date and time (date), displaying calendars (cal), and clearing the terminal screen (clear). It provides the syntax and examples for using each command.
The document provides an overview of basic and useful UNIX commands organized into categories including essential commands, valuable commands, fun commands, helpful commands, and useful commands. It describes commands for navigating directories, manipulating files, editing text, sending email, connecting to other systems, monitoring system usage, and more. The document is intended to help users get started with common tasks in UNIX.
This document provides an introduction to Linux, including:
- What Linux is and where it came from, as an open source operating system created by Linus Torvalds in 1991.
- How to get Linux through downloading a distribution like Red Hat and the packages it includes.
- Why Linux has become significant due to its growing popularity, ability to run on multiple hardware platforms, and being free.
- An overview of Linux commands and utilities for file management, processes, users and permissions.
This document provides a tutorial on common Linux commands. It lists commands like ls to list files, file to check file types, mkdir to make directories, cd to change directories, cp to copy, mv to move, and rm to remove files and directories. It also covers commands like cat to view file contents, grep to search files, more and less to page through large files, chown to change ownership, chmod to change permissions, ps to view processes, and kill and killall to terminate processes. The document explains that running "man [command]" provides documentation for each command.
This document provides a summary of the Unix and GNU/Linux command line. It begins with an overview of files and file systems in Unix, including that everything is treated as a file. It then discusses command line interpreters (shells), and commands for handling files and directories like ls, cd, cp, and rm. It also covers redirecting standard input/output, pipes, and controlling processes. The document is intended as training material and provides a detailed outline of its contents.
This document provides an introduction to useful Linux commands. It begins with a brief history of UNIX and Linux and describes the Linux directory structure. It then discusses commands for navigating directories, searching for files, manipulating text, basic networking, system information, disk usage monitoring, and more. The goal is to compile some essential Linux commands for newcomers to learn and get comfortable with.
Linux is a prominent example of free and open source software. It can be installed on a wide variety of devices from embedded systems to supercomputers. Linux is commonly used for servers, with estimates that it powers around 60% of web servers. Linux distributions package the Linux kernel with other software like utilities, libraries and desktop environments. Programming languages and build tools like GCC are supported. Embedded Linux is often used in devices due to its low cost and ease of modification.
This document provides a quick guide to the Linux command line. It introduces Linux and the shell, and explains why the command line is useful even with graphical user interfaces. It then covers basic commands for file management, processes, archives, and input/output redirection. Finally, it briefly mentions some simple text editors and hints at using more advanced shell scripting.
This lecture discusses the Environment Variables concept, usage, and how processes acquire them. It then goes through the most popular ones
Check the other Lectures and courses in
http://Linux4EnbeddedSystems.com
or Follow our Facebook Group at
- Facebook: @LinuxforEmbeddedSystems
Lecturer Profile:
- https://www.linkedin.com/in/ahmedelarabawy
Online Training in Unix Linux Shell Scripting in HyderabadRavikumar Nandigam
The document provides information about the UNIX operating system. It defines UNIX as a collection of software that manages computer hardware resources and provides common services. It then discusses examples of UNIX systems like DOS, Windows, MacOS, and Linux. It covers UNIX architecture including the kernel, shell, tools, and applications. It also summarizes important UNIX commands for system information, file manipulation, permissions, and viewing files.
This document provides a tutorial on Unix/Linux. It begins with an overview of the Unix system including the kernel, shell, multi-user and multi-process capabilities, and important directory structures. It then covers basic commands, relative and absolute paths, redirecting and piping output, permissions, process management, installing software, text editors, running jobs in the foreground and background, and remote login/file transfer. The goal is to introduce fundamental Unix concepts and commands to new users.
CompTIA Linux+ Powered by LPI certifies foundational skills and knowledge of Linux. With Linux being the central operating system for much of the world’s IT infrastructure, Linux+ is an essential credential for individuals working in IT, especially those on the path of a Web and software development career. With CompTIA’s Linux+ Powered by LPI certification, you’ll acquire the fundamental skills and knowledge you need to successfully configure, manage and troubleshoot Linux systems. Recommended experience for this certification includes CompTIA A+, CompTIA Network+ and 12 months of Linux admin experience. No prerequisites required.
Useful Linux and Unix commands handbookWave Digitech
This article provides practical examples for most frequently used commands in Linux / UNIX. Helpful for Engineers and trainee engineers, Software developers. A handy notes for all Linux & Unix commands.
- Linux originated as a clone of the UNIX operating system. Key developers included Linus Torvalds and developers from the GNU project.
- Linux is open source, multi-user, and can run on a variety of hardware. It includes components like the Linux kernel, shell, terminal emulator, and desktop environments.
- The document provides information on common Linux commands, files, users/groups, permissions, and startup scripts. It describes the Linux file system and compression/archiving utilities.
This document provides an overview of a presentation on Linux programming and administration. It covers the history of Unix and Linux, files and directories in Linux, Linux installation, basic Linux commands, user and group administration, and LILO (Linux Loader). The document introduces key topics like Unix flavors, Linux distributions, partitioning and formatting disks for Linux installation, the file system hierarchy standard, and access permissions in Linux.
The document provides an overview of common Linux commands, including commands for executing other commands, navigating directories, listing and copying files, managing users and permissions, searching for files, processing text, managing archives, and compressing files. Examples are given for commands like ls, cd, cp, mv, rm, who, echo, alias, awk, chown, diff, grep, pushd, kill, df, cat, tar, gzip, su. Brief descriptions are provided for most commands and references are given at the end for additional Linux resources.
This document provides an introduction and overview of the UNIX operating system. It discusses that UNIX is an operating system, like Windows, that manages communication between software and hardware. Popular versions of UNIX include Linux and Android. The document outlines reasons for using UNIX such as reliability, low/no cost, and open source access. It describes the core components of UNIX including the kernel, bootloader, daemons, and shells. Key features like being portable, multi-user, and providing security are highlighted. Common UNIX commands and utilities are listed along with file permissions, redirection, pipes, and filters.
What is Linux?
Command-line Interface, Shell & BASH
Popular commands
File Permissions and Owners
Installing programs
Piping and Scripting
Variables
Common applications in bioinformatics
Conclusion
Unix Shell Script - 2 Days Session.pptxRajesh Kumar
The document provides an overview of Unix and shell scripting. It discusses what Unix is, its architecture including the kernel, shell, commands, and filesystem. It then covers what shell scripts are, their components and syntax. The document provides examples of shell script code and discusses how to invoke scripts, execute them in background, and useful metacharacters. It also covers various Unix commands like ls, cd, grep, find and their usage.
The document provides an overview of Unix/Linux systems through a presentation given by Kuldeep Sharma. It covers the history of Unix and Linux, Linux shells, file types, basic commands for file navigation, text editing with vi, permissions, process management, and foreground vs background processes. Advantages of using Linux include low costs, stability, reliability, power and open source software, while disadvantages include a steep learning curve and limited hardware/application support.
Linux has become integral part of Embedded systems. This three part presentation gives deeper perspective of Linux from system programming perspective. Stating with basics of Linux it goes on till advanced aspects like thread and IPC programming.
This document provides an introduction and overview of Linux shell scripting. It discusses key topics like kernels, shells, processes, redirection, pipes, filters, variables, writing shell scripts, command line arguments, and more advanced shell scripting commands. The goal is to explain the basics of shell programming through examples of shell scripts. While it does not serve as a manual, it aims to provide more examples than typical manuals to clarify concepts for beginners.
This document provides an overview of Linux including:
- Different pronunciations of Linux and the origins of each pronunciation.
- A definition of Linux as a generic term for Unix-like operating systems with graphical user interfaces.
- Why Linux is significant as a powerful, free, and customizable operating system that runs on multiple hardware platforms.
- An introduction to key Linux concepts like multi-user systems, multiprocessing, multitasking and open source software.
- Examples of common Linux commands for file handling, text processing, and system administration.
Unix/Linux is an operating system developed in the 1960s that uses a command line interface. It is the predecessor to Linux, which is now a widely popular open-source variant of Unix. The document provides an overview of basic Unix/Linux commands and concepts for navigating files and directories, editing and manipulating files, running programs, and accessing remote systems. It explains commands like ls, cd, pwd, cat, less, grep, diff, kill, and scp.
Chapter 2 Introduction to Unix ConceptsMeenalJabde
The document provides an introduction to Unix concepts including:
1. It describes the architecture of Unix as having 4 layers - hardware, kernel, shell commands, and application layer. The kernel interacts with hardware and manages tasks like memory and process scheduling.
2. It lists some basic Unix commands like ls, echo, printf, who, date, passwd, cal and explains how to combine commands using operators like && and ||.
3. It explains Unix files and directories are organized in a hierarchical tree structure with the root directory at the top. There are different types of files like ordinary, special, pipes and symbolic links.
The document provides an overview of the Linux operating system. It discusses key Linux concepts like the kernel, shell, file structure, users and permissions. It also summarizes common Linux commands for file management, editing, users, groups, software installation and services. Key tools covered include vi editor, rpm, tar, useradd/del, service and chkconfig. The document is intended as part of an introductory Linux presentation.
The document outlines an upcoming Linux command line class, including:
- It will start with a sign-in sheet and end with a class evaluation.
- The class will cover as much material as possible in the allotted time, starting with the easiest concepts.
- It will be hands-on and allow questions at any time.
Here are some sed commands to demonstrate its capabilities:
◦ sed 's/rain/snow/' easy_sed.txt; cat easy_sed.txt
◦ sed 's/plain/mountains/' easy_sed.txt; cat easy_sed.txt
◦ sed 's/Spain/France/' easy_sed.txt; cat easy_sed.txt
◦ sed 's/^The //' easy_sed.txt; cat easy_sed.txt
◦ sed '/Spain/d' easy_sed.txt; cat easy_sed.txt
This demonstrates sed's substitution and deletion capabilities using regular expressions to match patterns in the file.
The document outlines an introductory class on using Linux at the command line. It will include:
- A sign-in sheet to collect student experience and goals
- Covering basic Linux commands and navigation
- Taking a break halfway through the class
- Ending with a class evaluation
The class is hands-on and students should ask questions. Commands will be shown in bold text for students to practice.
Here are some sed commands to demonstrate its capabilities:
◦ sed 's/rain/snow/' easy_sed.txt; cat easy_sed.txt
◦ sed 's/plain/mountains/' easy_sed.txt; cat easy_sed.txt
◦ sed 's/Spain/France/' easy_sed.txt; cat easy_sed.txt
◦ sed 's/^The //' easy_sed.txt; cat easy_sed.txt
◦ sed 's/ $//' easy_sed.txt; cat easy_sed.txt
◦ sed 's/plain$/plains/' easy_sed.txt; cat easy_
This document provides an overview of the Linux operating system. It discusses key Linux concepts like the kernel, shell, file system structure, permissions, users and groups. It also summarizes important commands for navigating and managing files, directories, users, software and services in Linux. These include commands like ls, cd, mkdir, chmod, useradd, yum, service and chkconfig. The document outlines the directory structure in Linux and describes important directories like /bin, /home, /etc. It also covers processes, pipes, redirection and Linux file systems & partitions.
This document provides an introduction to the UNIX/Linux operating system. It discusses general remarks about UNIX/Linux, including classification and essential features. It covers first steps at the computer such as user logon/logoff. It also discusses file systems, including file types, paths, and commands like pwd, ls, and cd.
This document provides an overview of an introductory class on using Linux at the command line. It outlines the following:
- The class will start with a sign-in sheet and end with an evaluation. The instructor will cover as much material as possible in the allotted time, starting with the easiest concepts.
- The class is hands-on and lab-based, allowing students to ask questions. Commands for students to type will be in bold text. There will be a mid-class break.
- Topics to be covered include basic Linux commands, navigating and manipulating files and directories, permissions, and using tools like grep, awk and sed to filter and manipulate output.
Linux Administration in this basic commands are there & also advanced commands are also there,It will be very use full for everyone who are all intrested in learning Linux,Which means everyone learn Linux esaliy.
This document provides an overview of Linux system fundamentals including how to install Ubuntu in a virtual machine, basic commands like ls, cat, and sudo, understanding users, home directories and man pages. It explains key Linux concepts such as the kernel, command line interface, and root user and how to switch directories, view files and get help using man pages.
Skybuffer AI: Advanced Conversational and Generative AI Solution on SAP Busin...Tatiana Kojar
Skybuffer AI, built on the robust SAP Business Technology Platform (SAP BTP), is the latest and most advanced version of our AI development, reaffirming our commitment to delivering top-tier AI solutions. Skybuffer AI harnesses all the innovative capabilities of the SAP BTP in the AI domain, from Conversational AI to cutting-edge Generative AI and Retrieval-Augmented Generation (RAG). It also helps SAP customers safeguard their investments into SAP Conversational AI and ensure a seamless, one-click transition to SAP Business AI.
With Skybuffer AI, various AI models can be integrated into a single communication channel such as Microsoft Teams. This integration empowers business users with insights drawn from SAP backend systems, enterprise documents, and the expansive knowledge of Generative AI. And the best part of it is that it is all managed through our intuitive no-code Action Server interface, requiring no extensive coding knowledge and making the advanced AI accessible to more users.
Digital Banking in the Cloud: How Citizens Bank Unlocked Their MainframePrecisely
Inconsistent user experience and siloed data, high costs, and changing customer expectations – Citizens Bank was experiencing these challenges while it was attempting to deliver a superior digital banking experience for its clients. Its core banking applications run on the mainframe and Citizens was using legacy utilities to get the critical mainframe data to feed customer-facing channels, like call centers, web, and mobile. Ultimately, this led to higher operating costs (MIPS), delayed response times, and longer time to market.
Ever-changing customer expectations demand more modern digital experiences, and the bank needed to find a solution that could provide real-time data to its customer channels with low latency and operating costs. Join this session to learn how Citizens is leveraging Precisely to replicate mainframe data to its customer channels and deliver on their “modern digital bank” experiences.
HCL Notes and Domino License Cost Reduction in the World of DLAUpanagenda
Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-and-domino-license-cost-reduction-in-the-world-of-dlau/
The introduction of DLAU and the CCB & CCX licensing model caused quite a stir in the HCL community. As a Notes and Domino customer, you may have faced challenges with unexpected user counts and license costs. You probably have questions on how this new licensing approach works and how to benefit from it. Most importantly, you likely have budget constraints and want to save money where possible. Don’t worry, we can help with all of this!
We’ll show you how to fix common misconfigurations that cause higher-than-expected user counts, and how to identify accounts which you can deactivate to save money. There are also frequent patterns that can cause unnecessary cost, like using a person document instead of a mail-in for shared mailboxes. We’ll provide examples and solutions for those as well. And naturally we’ll explain the new licensing model.
Join HCL Ambassador Marc Thomas in this webinar with a special guest appearance from Franz Walder. It will give you the tools and know-how to stay on top of what is going on with Domino licensing. You will be able lower your cost through an optimized configuration and keep it low going forward.
These topics will be covered
- Reducing license cost by finding and fixing misconfigurations and superfluous accounts
- How do CCB and CCX licenses really work?
- Understanding the DLAU tool and how to best utilize it
- Tips for common problem areas, like team mailboxes, functional/test users, etc
- Practical examples and best practices to implement right away
leewayhertz.com-AI in predictive maintenance Use cases technologies benefits ...alexjohnson7307
Predictive maintenance is a proactive approach that anticipates equipment failures before they happen. At the forefront of this innovative strategy is Artificial Intelligence (AI), which brings unprecedented precision and efficiency. AI in predictive maintenance is transforming industries by reducing downtime, minimizing costs, and enhancing productivity.
zkStudyClub - LatticeFold: A Lattice-based Folding Scheme and its Application...Alex Pruden
Folding is a recent technique for building efficient recursive SNARKs. Several elegant folding protocols have been proposed, such as Nova, Supernova, Hypernova, Protostar, and others. However, all of them rely on an additively homomorphic commitment scheme based on discrete log, and are therefore not post-quantum secure. In this work we present LatticeFold, the first lattice-based folding protocol based on the Module SIS problem. This folding protocol naturally leads to an efficient recursive lattice-based SNARK and an efficient PCD scheme. LatticeFold supports folding low-degree relations, such as R1CS, as well as high-degree relations, such as CCS. The key challenge is to construct a secure folding protocol that works with the Ajtai commitment scheme. The difficulty, is ensuring that extracted witnesses are low norm through many rounds of folding. We present a novel technique using the sumcheck protocol to ensure that extracted witnesses are always low norm no matter how many rounds of folding are used. Our evaluation of the final proof system suggests that it is as performant as Hypernova, while providing post-quantum security.
Paper Link: https://eprint.iacr.org/2024/257
A Comprehensive Guide to DeFi Development Services in 2024Intelisync
DeFi represents a paradigm shift in the financial industry. Instead of relying on traditional, centralized institutions like banks, DeFi leverages blockchain technology to create a decentralized network of financial services. This means that financial transactions can occur directly between parties, without intermediaries, using smart contracts on platforms like Ethereum.
In 2024, we are witnessing an explosion of new DeFi projects and protocols, each pushing the boundaries of what’s possible in finance.
In summary, DeFi in 2024 is not just a trend; it’s a revolution that democratizes finance, enhances security and transparency, and fosters continuous innovation. As we proceed through this presentation, we'll explore the various components and services of DeFi in detail, shedding light on how they are transforming the financial landscape.
At Intelisync, we specialize in providing comprehensive DeFi development services tailored to meet the unique needs of our clients. From smart contract development to dApp creation and security audits, we ensure that your DeFi project is built with innovation, security, and scalability in mind. Trust Intelisync to guide you through the intricate landscape of decentralized finance and unlock the full potential of blockchain technology.
Ready to take your DeFi project to the next level? Partner with Intelisync for expert DeFi development services today!
Dandelion Hashtable: beyond billion requests per second on a commodity serverAntonios Katsarakis
This slide deck presents DLHT, a concurrent in-memory hashtable. Despite efforts to optimize hashtables, that go as far as sacrificing core functionality, state-of-the-art designs still incur multiple memory accesses per request and block request processing in three cases. First, most hashtables block while waiting for data to be retrieved from memory. Second, open-addressing designs, which represent the current state-of-the-art, either cannot free index slots on deletes or must block all requests to do so. Third, index resizes block every request until all objects are copied to the new index. Defying folklore wisdom, DLHT forgoes open-addressing and adopts a fully-featured and memory-aware closed-addressing design based on bounded cache-line-chaining. This design offers lock-free index operations and deletes that free slots instantly, (2) completes most requests with a single memory access, (3) utilizes software prefetching to hide memory latencies, and (4) employs a novel non-blocking and parallel resizing. In a commodity server and a memory-resident workload, DLHT surpasses 1.6B requests per second and provides 3.5x (12x) the throughput of the state-of-the-art closed-addressing (open-addressing) resizable hashtable on Gets (Deletes).
GraphRAG for Life Science to increase LLM accuracyTomaz Bratanic
GraphRAG for life science domain, where you retriever information from biomedical knowledge graphs using LLMs to increase the accuracy and performance of generated answers
HCL Notes und Domino Lizenzkostenreduzierung in der Welt von DLAUpanagenda
Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-und-domino-lizenzkostenreduzierung-in-der-welt-von-dlau/
DLAU und die Lizenzen nach dem CCB- und CCX-Modell sind für viele in der HCL-Community seit letztem Jahr ein heißes Thema. Als Notes- oder Domino-Kunde haben Sie vielleicht mit unerwartet hohen Benutzerzahlen und Lizenzgebühren zu kämpfen. Sie fragen sich vielleicht, wie diese neue Art der Lizenzierung funktioniert und welchen Nutzen sie Ihnen bringt. Vor allem wollen Sie sicherlich Ihr Budget einhalten und Kosten sparen, wo immer möglich. Das verstehen wir und wir möchten Ihnen dabei helfen!
Wir erklären Ihnen, wie Sie häufige Konfigurationsprobleme lösen können, die dazu führen können, dass mehr Benutzer gezählt werden als nötig, und wie Sie überflüssige oder ungenutzte Konten identifizieren und entfernen können, um Geld zu sparen. Es gibt auch einige Ansätze, die zu unnötigen Ausgaben führen können, z. B. wenn ein Personendokument anstelle eines Mail-Ins für geteilte Mailboxen verwendet wird. Wir zeigen Ihnen solche Fälle und deren Lösungen. Und natürlich erklären wir Ihnen das neue Lizenzmodell.
Nehmen Sie an diesem Webinar teil, bei dem HCL-Ambassador Marc Thomas und Gastredner Franz Walder Ihnen diese neue Welt näherbringen. Es vermittelt Ihnen die Tools und das Know-how, um den Überblick zu bewahren. Sie werden in der Lage sein, Ihre Kosten durch eine optimierte Domino-Konfiguration zu reduzieren und auch in Zukunft gering zu halten.
Diese Themen werden behandelt
- Reduzierung der Lizenzkosten durch Auffinden und Beheben von Fehlkonfigurationen und überflüssigen Konten
- Wie funktionieren CCB- und CCX-Lizenzen wirklich?
- Verstehen des DLAU-Tools und wie man es am besten nutzt
- Tipps für häufige Problembereiche, wie z. B. Team-Postfächer, Funktions-/Testbenutzer usw.
- Praxisbeispiele und Best Practices zum sofortigen Umsetzen
Building Production Ready Search Pipelines with Spark and MilvusZilliz
Spark is the widely used ETL tool for processing, indexing and ingesting data to serving stack for search. Milvus is the production-ready open-source vector database. In this talk we will show how to use Spark to process unstructured data to extract vector representations, and push the vectors to Milvus vector database for search serving.
Monitoring and Managing Anomaly Detection on OpenShift.pdfTosin Akinosho
Monitoring and Managing Anomaly Detection on OpenShift
Overview
Dive into the world of anomaly detection on edge devices with our comprehensive hands-on tutorial. This SlideShare presentation will guide you through the entire process, from data collection and model training to edge deployment and real-time monitoring. Perfect for those looking to implement robust anomaly detection systems on resource-constrained IoT/edge devices.
Key Topics Covered
1. Introduction to Anomaly Detection
- Understand the fundamentals of anomaly detection and its importance in identifying unusual behavior or failures in systems.
2. Understanding Edge (IoT)
- Learn about edge computing and IoT, and how they enable real-time data processing and decision-making at the source.
3. What is ArgoCD?
- Discover ArgoCD, a declarative, GitOps continuous delivery tool for Kubernetes, and its role in deploying applications on edge devices.
4. Deployment Using ArgoCD for Edge Devices
- Step-by-step guide on deploying anomaly detection models on edge devices using ArgoCD.
5. Introduction to Apache Kafka and S3
- Explore Apache Kafka for real-time data streaming and Amazon S3 for scalable storage solutions.
6. Viewing Kafka Messages in the Data Lake
- Learn how to view and analyze Kafka messages stored in a data lake for better insights.
7. What is Prometheus?
- Get to know Prometheus, an open-source monitoring and alerting toolkit, and its application in monitoring edge devices.
8. Monitoring Application Metrics with Prometheus
- Detailed instructions on setting up Prometheus to monitor the performance and health of your anomaly detection system.
9. What is Camel K?
- Introduction to Camel K, a lightweight integration framework built on Apache Camel, designed for Kubernetes.
10. Configuring Camel K Integrations for Data Pipelines
- Learn how to configure Camel K for seamless data pipeline integrations in your anomaly detection workflow.
11. What is a Jupyter Notebook?
- Overview of Jupyter Notebooks, an open-source web application for creating and sharing documents with live code, equations, visualizations, and narrative text.
12. Jupyter Notebooks with Code Examples
- Hands-on examples and code snippets in Jupyter Notebooks to help you implement and test anomaly detection models.
Have you ever been confused by the myriad of choices offered by AWS for hosting a website or an API?
Lambda, Elastic Beanstalk, Lightsail, Amplify, S3 (and more!) can each host websites + APIs. But which one should we choose?
Which one is cheapest? Which one is fastest? Which one will scale to meet our needs?
Join me in this session as we dive into each AWS hosting service to determine which one is best for your scenario and explain why!
Introduction of Cybersecurity with OSS at Code Europe 2024Hiroshi SHIBATA
I develop the Ruby programming language, RubyGems, and Bundler, which are package managers for Ruby. Today, I will introduce how to enhance the security of your application using open-source software (OSS) examples from Ruby and RubyGems.
The first topic is CVE (Common Vulnerabilities and Exposures). I have published CVEs many times. But what exactly is a CVE? I'll provide a basic understanding of CVEs and explain how to detect and handle vulnerabilities in OSS.
Next, let's discuss package managers. Package managers play a critical role in the OSS ecosystem. I'll explain how to manage library dependencies in your application.
I'll share insights into how the Ruby and RubyGems core team works to keep our ecosystem safe. By the end of this talk, you'll have a better understanding of how to safeguard your code.
Ivanti’s Patch Tuesday breakdown goes beyond patching your applications and brings you the intelligence and guidance needed to prioritize where to focus your attention first. Catch early analysis on our Ivanti blog, then join industry expert Chris Goettl for the Patch Tuesday Webinar Event. There we’ll do a deep dive into each of the bulletins and give guidance on the risks associated with the newly-identified vulnerabilities.
This presentation provides valuable insights into effective cost-saving techniques on AWS. Learn how to optimize your AWS resources by rightsizing, increasing elasticity, picking the right storage class, and choosing the best pricing model. Additionally, discover essential governance mechanisms to ensure continuous cost efficiency. Whether you are new to AWS or an experienced user, this presentation provides clear and practical tips to help you reduce your cloud costs and get the most out of your budget.
How to Interpret Trends in the Kalyan Rajdhani Mix Chart.pdfChart Kalyan
A Mix Chart displays historical data of numbers in a graphical or tabular form. The Kalyan Rajdhani Mix Chart specifically shows the results of a sequence of numbers over different periods.
2. Credits
Cleveland Linux Users’ Group
Introduction to Linux (Jeff Gilton & Jim Weirich)
IBM
An Introduction to Linux (Al Henderson)
Why Linux is storming the market (Jonathan Prial)
Ivan Bowman
Conceptual software architecture of the Linux kernel
3. Contents
A quick guide to Linux
Background
Using Linux
S/390 Specifics
Linux in the Marketplace
Commercial Linux Applications
Additional Resources
4. What is Linux
A fully-networked 32/64-Bit Unix-like Operating System
Unix Tools Like sed, awk, and grep (explained later)
Compilers Like C, C++, Fortran, Smalltalk, Ada
Network Tools Like telnet, ftp, ping, traceroute
Multi-user, Multitasking, Multiprocessor
Has the X Windows GUI
Coexists with other Operating Systems
Runs on multiple platforms
Includes the Source Code
5. Where did it come from?
Linus Torvalds created it
with assistance from programmers around the
world
first posted on Internet in 1991
Linux 1.0 in 1994; 2.2 in 1999
Today used on 7-10 million computers
with 1000’s of programmers working to
enhance it
6. Open Source Software
When programmers on the Internet can
read, redistribute, and modify the source
for a piece of software, it evolves
People improve it, people adapt it, people
fix bugs. And this can happen at a speed
that, compared to conventional software
development, seems astonishing
7. How do you get it?
Download it from the Internet
From a “Distribution” (e.g. RedHat)
Linux kernel
X Windows system and GUI
Web, e-mail, FTP servers
Installation & configuration support
3rd party apps
Hardware support
8. Why is it significant?
Growing popularity
Powerful
Runs on multiple hardware platforms
Users like its speed and stability
No requirement for latest hardware
It’s “free”
Licensed under GPL
Vendors are distributors who package Linux
10. Logging In
Connect to the Linux system using telnet:
vt100, vt220, vt320
ansi
tty
X-windows
Able to login more than once with same
user
No ‘MW’ problems!
11. Logging In
Before you can use it you must login by
specifying your account and password:
Linux 2.2.13 (penguinvm.princeton.edu) (ttyp1)
penguinvm login: neale
Password:
Last login: Tue Jan 4 10:13:13 from
linuxtcp.princeton.edu
[neale@penguinvm neale]$
12. Rule Number 1
Do not login as root unless you have to
root is the system superuser (the “maint” of
Linux but more “dangerous”)
Normal protection mechanisms can be overridden
Careless use can cause damage
Has access to everything by default
root is the only user defined when you install
First thing is to change root’s password
The second job is to define “normal” users for
everyday use
13. Creating a new user
Use the useradd command
Use the passwd command to set
password
Try it… logon as root
[root@penguinvm]# useradd scully
[root@penguinvm]# passwd scully
Changing password for user scully
New UNIX password:
Retype new UNIX password:
passwd: all authentication tokens updated
successfully
[root@penguinvm]#
14. Adding a new user
Limits on users can be controlled by
Quotas
ulimit command
Authority levels for a user controlled by
group membership
15. Users and Groups
Users are identified by user identifications (UIDs), each
of which is associated with an integer in the range of 0
to 4 294 967 295 (X’FFFFFFFF’). Users with UID=0 are
given superuser privileges.
Users are placed in groups, identified by group
identifications (GIDs). Each GID is associated with an
integer in the range from 0 to 4 294 967 295
Let the system assign UID to avoid duplicates
Use id to display your user and group information
uid=500(neale) gid=500(neale) groups=500(neale),3(sys),4(adm)
16. Users and Groups
Groups define functional areas/responsibilities
They allow a collection of users to share files
A user can belong to multiple groups
You can see what groups you belong to using
the groups command:
neale sys adm
18. Using the new user
Now logoff using the exit command
login as the new user
Linux 2.2.13 (penguinvm.princeton.edu) (ttyp2)
penguinvm login: scully
Password:
[scully@penguinvm scully]$
19. You need help?
The Linux equivalent of HELP is man
(manual)
Use man -k <keyword> to find all
commands with that keyword
Use man <command> to display help for that
command
Output is presented a page at a time. Use b for to
scroll backward, f or a space to scroll forward and
q to quit
20. The Linux System
User commands includes executable
programs and scripts
The shell interprets user commands. It is User commands
responsible for finding the commands
and starting their execution. Several Shell
different shells are available. Bash is
popular, Kernel File Systems
Device Drivers
The kernel manages the hardware resources Hardware
for the rest of the system.
21. Linux File System Basics
Linux files are stored Directories root
in a single rooted,
hierarchical file
system
Data files are stored
in directories (folders)home
User
Directories may bedirectories
nested as deep as
needed
Data files
22. Naming Files
Files are named by
naming each
containing directory
starting at the root
This is known as the
pathname /etc/passwd
/home/neale/b
23. The Current Directory
One directory is
designated the
current working
directory
if you omit the
leading / then path
name is relative to the
current working
directory
Use pwd to find out
where youCurrent
are
working
directory doc/letter
./doc/letter
/home/neale/doc/letter
24. Some Special File Names
Some file names are special:
/ The root directory (not to be confused with the root user)
. The current directory
.. The parent (previous) directory
~ My home directory
Examples:
./a same as a
../jane/x go up one level then look in directory jane for x
25. Special Files
/home - all users’ home directories are stored
here
/bin, /usr/bin - system commands
/sbin, /usr/sbin - commands used by
sysadmins
/etc - all sorts of configuration files
/var - logs, spool directories etc.
/dev - device files
/proc - special system files
26. Linux Command Basics
To execute a command, type its name
and arguments at the command line
ls -l /etc
Command name Arguments
Options
(flags)
27. Standard Files
UNIX concept of “standard files”
standard input (where a command gets its
input) - default is the terminal
standard output (where a command writes it
output) - default is the terminal
standard error (where a command writes
error messages) - default is the terminal
28. Redirecting Output
The output of a command may be sent
(piped) to a file:
ls -l >output
“>” is used to specify
the output file
29. Redirecting Input
The input of a command may come (be
piped) from a file:
wc <input
“<” is used to specify
the input file
30. Connecting commands
with Pipes
Not as powerful as CMS Pipes but the
same principle
The output of one command can become
the input of another: Like CMS Pipes, “|” is
used to separate stages
ps aux | grep netscape | wc -l
The output of the ps wc takes this input and
command is sent to counts the lines its output
grep going to the console
grep takes input and searches for
“netscape” passing these lines to wc
31. Command Options
Command options allow you to control a
command to a certain degree
Conventions:
Usually being with a single dash and are a
single letter (“-l”)
Sometimes have double dashes followed by a
keyword (“--help”)
Sometimes follow no pattern at all
32. Common Commands
pwd - print (display) the working directory
cd <dir> - change the current working
directory to dir
ls - list the files in the current working directory
ls -l - list the files in the current working
directory in long format
33. File Commands
cp <fromfile> <tofile>
Copy from the <fromfile> to the <tofile>
mv <fromfile> <tofile>
Move/rename the <fromfile> to the <tofile>
rm <file>
Remove the file named <file>
mkdir <newdir>
Make a new directory called <newdir>
rmdir <dir>
Remove an (empty) directory
34. More Commands
who
List who is currently logged on to the system
whoami
Report what user you are logged on as
ps
List your processes on the system
ps aux
List all the processes on the system
echo “A string to be echoed”
Echo a string (or list of arguments) to the terminal
35. More Commands
alias - used to tailor commands:
alias erase=rm
alias grep=”grep -i”
ar - Maintain archive libraries: a
collection of files (usually object files
which may be linked to a program, like a
CMS TXTLIB)
ar -t libgdbm.a
__.SYMDEF
dbmopen.o
36. More Commands
awk - a file processing language that is
well suited to data manipulation and
retrieval of information from text files
chown - sets the user ID (UID) to owner
for the files and directories named by
pathname arguments. This command is
useful when from test to production
chown -R apache:httpd /usr/local/apache
37. More Commands
diff - attempts to determine the minimal
set of changes needed to convert a file
specified by the first argument into the file
specified by the second argument
find - Searches a given file hierarchy
specified by path, finding files that match
the criteria given by expression
38. More Commands
grep - Searches files for one or more
pattern arguments. It does plain string,
basic regular expression, and extended
regular expression searching
find ./ -name "*.c" | xargs grep -i "fork"
In this example, we look for files with an extension “c” (that is, C source files). The filenames we
find are passed to the xargs command which takes these names and constructs a command line
of the form: grep -i fork <file.1>…<file.n>. This command will search the files for the
occurrence of the string “fork”. The “-i” flag makes the search case insensitve.
39. More Commands
kill - sends a signal to a process or
process group
You can only kill your own processes
unless you are root
UID PID PPID C STIME TTY TIME CMD
root 6715 6692 2 14:34 ttyp0 00:00:00 sleep 10h
root 6716 6692 0 14:34 ttyp0 00:00:00 ps -ef
[root@penguinvm log]# kill 6715
[1]+ Terminated sleep 10h
40. More Commands
make - helps you manage projects
containing a set of interdependent files
(e.g. a program with many source and
object files; a document built from source
files; macro files)
make keeps all such files up to date with
one another: If one file changes, make
updates all the other files that depend on
the changed file
Roughly the equivalent of VMFBLD
41. More Commands
sed - applies a set of editing subcommands
contained in a script to each argument input
file
find ./ -name "*.c,v" | sed ’s/,v//g’ | xargs grep "PATH"
This finds all files in the current and subsequent directories with an extension of c,v. sed
then strips the ,v off the results of the find command. xargs then uses the results of sed
and builds a grep command which searches for occurrences of the word PATH in the C
source files.
42. More Commands
tar - manipulates archives
An archive is a single file that contains the
complete contents of a set of other files; an
archive preserves the directory hierarchy that
contained the original files. Similary to a
VMARC file
tar -tzf imap-4.7.tar.gz
imap-4.7/
imap-4.7/src/
imap-4.7/src/c-client/
imap-4.7/src/c-client/env.h
imap-4.7/src/c-client/fs.h
43. Shells
An interface between the Linux system
and the user
Used to call commands and programs
An interpreter
Powerful programming language
“Shell scripts” = .bat .cmd EXEC REXX
Many available (bsh; ksh; csh; bash; tcsh)
44. Another definition of a Shell
A shell is any program that takes input
from the user, translates it into instructions
that the operating system can understand,
and conveys the operating system's
output back to the user.
• i.e. Any User Interface
• Character Based v Graphics Based
45. Why Do I Care About
The Shell?
Shell is Not Integral Part of OS
UNIX Among First to Separate
Compare to MS-DOS, Mac, Win95, VM/CMS
GUI is NOT Required
Default Shell Can Be Configured
chsh -s /bin/bash
/etc/passwd
Helps To Customize Environment
46. Shell Scripts
#!/bin/bash
while
true
do
cat somefile > /dev/null
echo .
done
/* */
do forever
‘PIPE < SOME FILE | hole’
say ‘.’
end
47. Switching Users
su <accountname>
switch user accounts. You will be prompted for a
password. When this command completes, you will
be logged into the new account. Type exit to return
to the previous account
su
Switch to the root user account. Do not do this lightly
Note: The root user does not need to enter a password when
switching users. It may become any user desired. This is part of the
power of the root account.
48. Environment Variables
Environment variables are global settings
that control the function of the shell and
other Linux programs. They are sometimes
referred to global shell variables.
Setting:
VAR=/home/fred/doc
export TERM=ansi
SYSTEMNAME=`uname -n`
Similar to GLOBALV SET … in CMS
49. Environment Variables
Using Environment Variables:
echo $VAR
cd $VAR
cd $HOME
echo “You are running on $SYSTEMNAME”
Displaying - use the following commands:
set (displays local & env. Vars)
export
Vars can be retrieved by a script or a program
50. Some Important
Environment Variables
HOME
Your home directory (often be abbreviated as “~”)
TERM
The type of terminal you are running (for example
vt100, xterm, and ansi)
PWD
Current working directory
PATH
List of directories to search for commands
51. PATH Environment Variable
Controls where commands are found
PATH is a list of directory pathnames separated
by colons. For example:
PATH=/bin:/usr/bin:/usr/X11R6/bin:/u
sr/local/bin:/home/scully/bin
If a command does not contain a slash, the shell
tries finding the command in each directory in
PATH. The first match is the command that will
run
52. PATH Environment Variable
Similar to setting the CMS search order
Usually set in /etc/profile (like the
SYSPROF EXEC)
Often modified in ~/.profile (like the
PROFILE EXEC)
53. File Permissions
Every file
Is owned by someone
Belongs to a group
Has certain access permissions for owner,
group, and others
Default permissions determined by umask
54. File Permissions
Every user:
Has a uid (login name), gid (login group) and
membership of a "groups" list:
The uid is who you are (name and number)
The gid is your initial “login group” you normally
belong to
The groups list is the file groups you can access
via group permissions
55. File Permissions
Linux provides three kinds of permissions:
Read - users with read permission may read
the file or list the directory
Write - users with write permission may write
to the file or new files to the directory
Execute - users with execute permission may
execute the file or lookup a specific file within
a directory
56. File Permissions
The long version of a file listing (ls -l)
will display the file permissions:
-rwxrwxr-x 1 rvdheij rvdheij 5224 Dec 30 03:22 hello
-rw-rw-r-- 1 rvdheij rvdheij 221 Dec 30 03:59 hello.c
-rw-rw-r-- 1 rvdheij rvdheij 1514 Dec 30 03:59 hello.s
drwxrwxr-x 7 rvdheij rvdheij 1024 Dec 31 14:52 posixuft
Permissions Group
Owner
57. Interpreting File Permissions
-rwxrwxrwx
Other permissions
Group permissions
Owner permissions
Directory flag (d=directory; l=link)
58. Changing File Permissions
Use the chmod command to change file
permissions
The permissions are encoded as an octal
number
chmod 755 file # Owner=rwx Group=r-x Other=r-x
chmod 500 file2 # Owner=r-x Group=--- Other=---
chmod 644 file3 # Owner=rw- Group=r-- Other=r--
chmod +x file # Add execute permission to file for all
chmod o-r file # Remove read permission for others
chmod a+w file # Add write permission for everyone
59. Links?
Links are references to files (aliases)
Two forms:
Hard
Symbolic
Can point to files on different physical devices
Delete of original leaves link
Delete of link leaves original
Can be created for directories
Create using ln command
60. Editors
People are fanatical about their editor
Several choices available:
vi Standard UNIX editor
the XEDIT-like editor
xedit X windows text editor
emacs Extensible, Customizable Self-
Documenting Display Editor
pico Simple display-oriented text editor
nedit X windows Motif text editor
61. Linux Device Handling
Devices are the way linux talks to the world
Devices are special files in the /dev
directory (try ls /dev)
/dev/ttyx TTY devices
/dev/hdb IDE hard drive
/dev/hdb1 Partition 1 on the IDE hard drive
/dev/mnda VM Minidisk
/dev/dda Channel Attached DASD
/dev/dda1 Partition 1 on DASD
/dev/null The null device (“hole”)
/dev/zero An endless stream of zeroes
/dev/mouse Link to mouse (not /390)
62. Devices and Drivers
Each /dev file has a major and minor
number
Major defines the device type
Minor defines device within that type
Drivers register a device type
brw-r--r-- 1 root root 64, 0 Jun 1 1999 /dev/mnda
crw-r--r-- 1 root root 5, 0 Jan 5 09:18 /dev/tty
Device Type:
b - block Major no. Minor no.
c - character
63. Special Files - /proc
Information about internal Linux
processes are accessible to users via
the /proc file system (in memory)
/ proc/ cpuinfo CPU Information
/ proc/ interrupts Interrupt usage
/ proc/ version Kernel version
/ proc/ modules Active modules
cat /proc/cpuinfo
vendor_id : IBM/S390
# processors : 1
bogomips per cpu: 86.83
processor 0: version = FF, identification = 045226, machine = 9672
64. File Systems
Linux supports many different types
Most commonly, ext2fs
Filenames of 255 characters
File sizes up to 2GB
Theoretical limit 4TB
Derived from extfs
Highly reliable and high performer
66. File Systems
mount
Mounts a file system that lives on a device to
the main file tree
Start at Root file system
Mount to root
Mount to points currently mounted to root
/etc/fstab used to establish boot time
mounting
67. Virtual File System
VFS is designed to present a consistent
view of data as stored on hardware
Almost all hardware devices are
represented using a generic interface
VFS goes further, allowing the sysadmin
to mount any of a set of logical file
systems on any physical device
68. Virtual File System
Logical file systems promote compatibility
with other operating system standards
permitting developers to implement file
systems with different policies
VFS abstracts details of physical device
and logical file system allowing processes
to access files using a common interface,
without knowing what physical or logical
system the file resides on
69. Virtual File System
Analogous to CMS:
SFS
Minidisks
Two different designs
Common/transparent access
70.
71. Processes
Processes are created in a hierarchical structure whose
depth is limited only by the virtual memory available to
the virtual machine
A process may control the execution of any of its
descendants by suspending or resuming it, altering its
relative priority, or even terminating it
Termination of a process by default causes termination
of all its descendants; termination of the root process
causes termination of the session
Linux assigns a process ID (PID) to the process
72. Processes
Foreground
When a command is executed from the prompt and
runs to completion at which time the prompt returns is
said to run in the foreground
Background
When a command is executed from the prompt with
the token “&” at the end of the command line, the
prompt immediately returns while the command
continues is said to run in the background
73. Processes
Daemons
Background processes for system
administration are referred to as “daemons”
These processes are usually started during
the boot process
The processes are not assigned any
terminals PPID C STIME TTY
UID PID TIME CMD
root 5 1 0 1999 ? 00:00:14 [kswapd]
bin 254 1 0 1999 ? 00:00:00 [portmap]
root 307 1 0 1999 ? 00:00:23 syslogd -m 0
root 350 1 0 1999 ? 00:00:34 httpd
74. Processes
& causes process to be run
in “background”
[root@penguinvm log]# sleep 10h &
[1] 6718
[root@penguinvm log]# ps -ef
UID PID PPID C STIME TTY TIME CMD
root 6718 6692 0 14:49 ttyp0 00:00:00 sleep 10h
Job Number Process ID (ID) Parent Process ID
75. Processes - UID & GID
Real UID
At process creation, the real UID identifies the
user who has created the process
Real GID
At process creation, the real GID identifies
the current connect group of the user for
which the process was created
76. Processes - UID & GID
Effective UID
The effective UID is used to determine owner access
privileges of a process.
Normally the same as the real UID. It is possible for a
program to have a special flag set that, when this
program is executed, changes the effective UID of
the process to the UID of the owner of the program.
A program with this special flag set is said to be a
set-user-ID program (SUID). This feature provides
additional permissions to users while the SUID
program is being executed.
77. Processes - UID & GID
Effective GID
Each process also has an effective group
The effective GID is used to determine group access
privileges of a process
Normally the same as the real GID. A program can
have a special flag set that, when this program is
executed, changes the effective GID of the process to
the GID of the owner of this program
A program with this special flag set is said to be a
set-group-ID program (SGID). Like the SUID feature,
this provides additional permission to users while the
set-group-ID program is being executed
78. Processes - Process Groups
Each process belongs to a process group
A process group is a collection of one or more
processes
Each process group has a unique process group ID
It is possible to send a signal to every process in the
group just by sending the signal to the process group
leader
Each time the shell creates a process to run an
application, the process is placed into a new process
group
When an application spawns new processes, these are
members of the same process group as the parent
79. Processes - PID
PID
A process ID is a unique identifier assigned to
a process while it runs
Each time you run a process, it has a different
PID (it takes a long time for a PID to be
reused by the system)
You can use the PID to track the status of a
process with the ps command or the jobs
command, or to end a process with the kill
command
80. Processes - PGID
PGID
Each process in a process group shares a
process group ID (PGID), which is the same
as the PID of the first process in the process
group
This ID is used for signaling-related
processes
If a command starts just one process, its PID
and PGID are the same
81. Processes - PPID
PPID
A process that creates a new process is
called a parent process; the new process is
called a child process
The parent process (PPID) becomes
associated with the new child process when it
is created
The PPID is not used for job control
82. Security Guidelines
Take Care With Passwords
Use good ones (motherhood statement)
Don't Use Real Words
Make Sure They Are Not Easily Guessed
Use Combinations Of Upper and Lower Case,
Numbers, Punctuation
One Method: Take first letter of a sentence or
book title, insert numbers and punctuation.
83. Security Guidelines
Take care of passwords (continued)
Use Shadow Passwords
Allows encrypted passwords to be in a file that is
not world readable
Use Password Aging
Requires shadow passwords
84. Security Guidelines
Restrict Superuser Access
Restrict where root can log in from
/etc/securetty restricts root access to devices
listed
Use wheel group to restrict who can su to
root
Put users who can su to root in wheel group in
/etc/group file.
85. Security Guidelines
Use groups to allow access to files that
must be shared
Otherwise users will set world permission
Be careful with SUID and SGID
Avoid setting executables to SUID root
Wrap SUID root wrapper around programs if
they must be run SUID root
Create special accounts for programs that
must run with higher permissions
86. Security - Important Files
/etc/passwd - password file
/etc/shpasswd - shadow password file
/etc/group -lists groups and users contained in groups
/etc/services - lists network services and their ports
/etc/ftpusers - contains list of accounts that cannot use ftp
/etc/hosts.equiv - generic list of remote users
~/.rhosts - list of remote users for a specific account
/etc/hosts - host definition list
/etc/hosts.lpd - hosts who can use remote printing
/etc/hosts.allow - lists services that remote users are allowed to use
/etc/hosts.deny - lists services tthat remote users are not allowed to use
/etc/nologin - no login message that also disables logins
/etc/securetty - lists legal terminals for root to login from
/etc/exports - lists locations that can be remotely accessed via NFS
/etc/syslog.conf - configures the syslog facility
/etc/inetd.conf - configures inetd
87. Linux/390 Specifics
An ASCII implementation
Adds a layer of abstraction to I/O
Channel based v IRQ based
Support for ECKD using SSCH
Support for VM minidisks (ECKD, CKD,
FBA, VDISK)
88. Linux/390 Specifics
Runs natively, in LPAR, or under VM/ESA
Uses relative instructions: G2, P/390,
R/390 or better
Will use hardware IEEE FP or will emulate
Network drivers for CTCA/ESCON, OSA-
2, and IUCV (VM only)
3215 emulation for virtual console
Hardware console driver (HMC)
90. Linux in the Business
World
Issues and observations
91. Linux’s place in the market
The business world is interested in:
Efficiency and effectiveness
Networked economy
Network-based businesses
92. Linux’s place in the market
The world is heterogeneous
90% of Fortune 1000 companies use 3 or more
Operating Systems
The demands of e-business
Integrates with existing investments
Supports any client
Applications built/deployed independent of client
24 x 7
93. Linux’s place in the market
Importance of the application model
Server-centric and based on standards that
span multiple platforms
Leverage core business systems and scale to
meet unpredictable demands
Quick to deploy, easy to use and manage
94. Linux’s place in the market
ISVs which have made Linux
announcements:
BEA; Novell; SAP; Informix; Oracle, IBM; HP;
CA; ApplixWare; Star; Corel; Cygnus;
MetroWerks; ObjectShare; Inprise
Media spotlight:
CNN; PCWorld; PCWeek; InternetWeek
95. Linux’s place in the market
Early commercial users
Cendant Corporation - 4000 hotels
Burlington Coat Factory - back office functions
Northwest Airlines - 23 flight simulators
Intel announcement January 5 2000
New web appliances to run Linux
At the insistence of customers (e.g. NEC)
96. Linux’s place in the market
Impacts:
Applications:
Webservers (65%)
WebInfrastructure (mail, DNS) (15%)
File/Print (15%)
DB & DB Applications (2%)
Observations
Linux/Apache share of Web serving high
Autonomous departments
Many SMB and small ISP
CIOs discovering they have Linux running somewhere
Strong mindshare among developers
97. Linux’s place in the market
Linux’s appeal
Embraces new generation of web-based apps
Player in the heterogeneous e-business world
Provides flexibility and choice of environment
Open Source focuses on open standards
98. Linux’s place in the market
Challenges for growth
Products/Technologies/Offerings
Support services
ISV applications
Service providers
Trends
Movement to mainstream
Standards
Ease of use
99. IBM’s focus on Linux
Services Support offering; Curriculum
Software Porting all key products to Linux
Hardware Intel; RS/ 6000; S/ 390
Alliances Partner with Caldera; Redhat;
SuSe
Open Source Support standards & contribute to
bodies
100. IBM Software Announcements
DB2 Universal Database
Transarc AFS (distributed file system)
On Demand Server
Lotus Domino R5
WebSphere
Tivoli
101. Linux’s place in the market
Summary
Linux is viable in many key application areas
Linux has moved from small technical
projects to significant deployment
IBM claims to be fully supportive of Linux
Part of their heterogeneous strategy
Open source supporter
Hardware, software, and service offerings
103. Website Development
ASWedit, HTML VirtuFlex 1.1
editor Visual prolog
Empress DataWEB Web Crossing
EZ-EDIT ThreadTrack
LinkScan WebTailor from
TalentSoft Web+ Webthreads.
(WebPlus)
104. Databases
c-tree Plus Qddb
Empress Raima Database
Essentia Manager++
FairCom Server Empress Embedded
INFORMIX-SE RDBMS
SOLID Server
Just Logic/SQL
Velocis Database
KE Texpress
Server
Yard SQL
105. Data Visualization and CAD
IDL (Interactive Data Language)
Megahedron
Tecplot 7.0
VariCAD
VARKON
XVScan
106. Development Tools
ACUCOBOL-GT Finesse
Amzi! Prolog & Logic ISE Eiffel
Server EiffelBench
Basmark QuickBASIC C-Forge IDE
Critical Mass CM3 IdeaFix
Dynace j-tree
Absoft Fortran 77 KAI C++
Khoros Pro 2.1
107. Development Tools
MetaCard SEDIT, S/REXX
ObjectManual Rel 3.0 SNiFF+
Critical Mass Reactor ST/X (Smalltalk/X)
Resource Standard tdb (Tcl Debugger)
Metrics tprof (Tcl Profiler)
r-tree View Designer/X
sdoc (Source (VDX)
Documenter) XBasic
XMove 4.0 for Linux
110. Libraries
FontScope
INTERACTER
Matrix<LIB> - C++ Math Matrix Library
PKWARE Data Compression Library for
Linux
readyBase
SIMLIB IG
111. Mathematics
Maple V Release 4 - The Power Edition
MATCOM and MATCOM MATH LIBRARY
Mathematica 3.0
MATLAB and Simulink
112. Multimedia
Peter Lipa and his Journeys
Lucka Vondrackova and her Journeys
MpegTV Player 1.0
Peter Nagy and his Journeys
Xaudio
113. Network Servers
Critical Angle X.500 Enabler
DNEWS News Server
Aventail Internet Policy Manager
Aventail VPN
WANPIPE
Zeus Web Server
114. Office Tools
Corel WordPerfect 8 Axene Office
The American Heritage Projector and
Dictionary Deluxe Projector/Net
Applixware Office Suite The Virtual Office
D.M.S. Document System
Management System Axene XAllWrite
HotWire EasyFAX Axene Xclamation
NExS, the Network Axene XQuad
Extensible
Spreadsheet
117. X Windows Related
Accelerated-X MaXimum cde
Display Server Developer's Edition
BXwidgets v1.0
BXwidgets/DB Multi-headed,
Accelerated-X Display
Laptop, Accelerated-
X Display Server Server
OpenGL, Accelerated-
X Display Server
OSF-Certified Motif
119. Additional Resources
UNIX Systems Administrator Resources
http://www.ugu.com/
Linux/390 Observations and Notes
http://penguinvm.princeton.edu
Introduction to Linux
Introduction to UNIX
Linux/390 Installation
Linux Administration Made Easy
http://www.linuxninja.com/linux-admin/book1.html
Conceptual software architecture of the Linux kernel