Unix Systems: Shell Scripting (I)
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Fundamentals of UNIX Lab 5.4.6 – Listing Directory Information (Estimated Time: 30 Min.)
Fundamentals of UNIX Lab 5.4.6 – Listing Directory Information (Estimated time: 30 min.) Objectives: • Learn to display directory and file information • Use the ls (list files) command with various options • Display hidden files • Display files and file types • Examine and interpret the results of a long file listing • List individual directories • List directories recursively Background: In this lab, the student will use the ls command, which is used to display the contents of a directory. This command will display a listing of all files and directories within the current directory or specified directory or directories. If no pathname is given as an argument, ls will display the contents of the current directory. The ls command will list any subdirectories and files that are in the current working directory if a pathname is specified. The ls command will also default to a wide listing and display only file and directory names. There are many options that can be used with the ls command, which makes this command one of the more flexible and useful UNIX commands. Command Format: ls [-option(s)] [pathname[s]] Tools / Preparation: a) Before starting this lab, the student should review Chapter 5, Section 4 – Listing Directory Contents b) The student will need the following: 1. A login user ID, for example user2, and a password assigned by their instructor. 2. A computer running the UNIX operating system with CDE. 3. Networked computers in classroom. Notes: 1 - 5 Fundamentals UNIX 2.0—-Lab 5.4.6 Copyright 2002, Cisco Systems, Inc. Use the diagram of the sample Class File system directory tree to assist with this lab. -
Network Monitoring & Management Using Cacti
Network Monitoring & Management Using Cacti Network Startup Resource Center www.nsrc.org These materials are licensed under the Creative Commons Attribution-NonCommercial 4.0 International license (http://creativecommons.org/licenses/by-nc/4.0/) Introduction Network Monitoring Tools Availability Reliability Performance Cact monitors the performance and usage of devices. Introduction Cacti: Uses RRDtool, PHP and stores data in MySQL. It supports the use of SNMP and graphics with RRDtool. “Cacti is a complete frontend to RRDTool, it stores all of the necessary information to create graphs and populate them with data in a MySQL database. The frontend is completely PHP driven. Along with being able to maintain Graphs, Data Sources, and Round Robin Archives in a database, cacti handles the data gathering. There is also SNMP support for those used to creating traffic graphs with MRTG.” Introduction • A tool to monitor, store and present network and system/server statistics • Designed around RRDTool with a special emphasis on the graphical interface • Almost all of Cacti's functionality can be configured via the Web. • You can find Cacti here: http://www.cacti.net/ Getting RRDtool • Round Robin Database for time series data storage • Command line based • From the author of MRTG • Made to be faster and more flexible • Includes CGI and Graphing tools, plus APIs • Solves the Historical Trends and Simple Interface problems as well as storage issues Find RRDtool here:http://oss.oetiker.ch/rrdtool/ RRDtool Database Format General Description 1. Cacti is written as a group of PHP scripts. 2. The key script is “poller.php”, which runs every 5 minutes (by default). -
Munin Documentation Release 2.0.44
Munin Documentation Release 2.0.44 Stig Sandbeck Mathisen <[email protected]> Dec 20, 2018 Contents 1 Munin installation 3 1.1 Prerequisites.............................................3 1.2 Installing Munin...........................................4 1.3 Initial configuration.........................................7 1.4 Getting help.............................................8 1.5 Upgrading Munin from 1.x to 2.x..................................8 2 The Munin master 9 2.1 Role..................................................9 2.2 Components.............................................9 2.3 Configuration.............................................9 2.4 Other documentation.........................................9 3 The Munin node 13 3.1 Role.................................................. 13 3.2 Configuration............................................. 13 3.3 Other documentation......................................... 13 4 The Munin plugin 15 4.1 Role.................................................. 15 4.2 Other documentation......................................... 15 5 Documenting Munin 21 5.1 Nomenclature............................................ 21 6 Reference 25 6.1 Man pages.............................................. 25 6.2 Other reference material....................................... 40 7 Examples 43 7.1 Apache virtualhost configuration.................................. 43 7.2 lighttpd configuration........................................ 44 7.3 nginx configuration.......................................... 45 7.4 Graph aggregation -
Automatic Placement of Authorization Hooks in the Linux Security Modules Framework
Automatic Placement of Authorization Hooks in the Linux Security Modules Framework Vinod Ganapathy [email protected] University of Wisconsin, Madison Joint work with Trent Jaeger Somesh Jha [email protected] [email protected] Pennsylvania State University University of Wisconsin, Madison Context of this talk Authorization policies and their enforcement Three concepts: Subjects (e.g., users, processes) Objects (e.g., system resources) Security-sensitive operations on objects. Authorization policy: A set of triples: (Subject, Object, Operation) Key question: How to ensure that the authorization policy is enforced? CCS 2005 Automatic Placement of Authorization Hooks in the Linux Security Modules Framework 2 Enforcing authorization policies Reference monitor consults the policy. Application queries monitor at appropriate locations. Can I perform operation OP? Reference Monitor Application to Policy be secured Yes/No (subj.,obj.,oper.) (subj.,obj.,oper.) (subj.,obj.,oper.) (subj.,obj.,oper.) (subj.,obj.,oper.) CCS 2005 Automatic Placement of Authorization Hooks in the Linux Security Modules Framework 3 Linux security modules framework Framework for authorization policy enforcement. Uses a reference monitor-based architecture. Integrated into Linux-2.6 Linux Kernel Reference Monitor Policy (subj.,obj.,oper.) (subj.,obj.,oper.) (subj.,obj.,oper.) (subj.,obj.,oper.) (subj.,obj.,oper.) CCS 2005 Automatic Placement of Authorization Hooks in the Linux Security Modules Framework 4 Linux security modules framework Reference monitor calls (hooks) placed appropriately in the Linux kernel. Each hook is an authorization query. Linux Kernel Reference Monitor Policy (subj.,obj.,oper.) (subj.,obj.,oper.) (subj.,obj.,oper.) (subj.,obj.,oper.) (subj.,obj.,oper.) Hooks CCS 2005 Automatic Placement of Authorization Hooks in the Linux Security Modules Framework 5 Linux security modules framework Authorization query of the form: (subj., obj., oper.)? Kernel performs operation only if query succeeds. -
Masked Graph Modeling for Molecule Generation ✉ Omar Mahmood 1, Elman Mansimov2, Richard Bonneau 3 & Kyunghyun Cho 2
ARTICLE https://doi.org/10.1038/s41467-021-23415-2 OPEN Masked graph modeling for molecule generation ✉ Omar Mahmood 1, Elman Mansimov2, Richard Bonneau 3 & Kyunghyun Cho 2 De novo, in-silico design of molecules is a challenging problem with applications in drug discovery and material design. We introduce a masked graph model, which learns a dis- tribution over graphs by capturing conditional distributions over unobserved nodes (atoms) and edges (bonds) given observed ones. We train and then sample from our model by iteratively masking and replacing different parts of initialized graphs. We evaluate our 1234567890():,; approach on the QM9 and ChEMBL datasets using the GuacaMol distribution-learning benchmark. We find that validity, KL-divergence and Fréchet ChemNet Distance scores are anti-correlated with novelty, and that we can trade off between these metrics more effec- tively than existing models. On distributional metrics, our model outperforms previously proposed graph-based approaches and is competitive with SMILES-based approaches. Finally, we show our model generates molecules with desired values of specified properties while maintaining physiochemical similarity to the training distribution. 1 Center for Data Science, New York University, New York, NY, USA. 2 Department of Computer Science, Courant Institute of Mathematical Sciences, New ✉ York, NY, USA. 3 Center for Genomics and Systems Biology, New York University, New York, NY, USA. email: [email protected] NATURE COMMUNICATIONS | (2021) 12:3156 | https://doi.org/10.1038/s41467-021-23415-2 | www.nature.com/naturecommunications 1 ARTICLE NATURE COMMUNICATIONS | https://doi.org/10.1038/s41467-021-23415-2 he design of de novo molecules in-silico with desired prop- enable more informative comparisons between models that use Terties is an essential part of drug discovery and materials different molecular representations. -
Your Performance Task Summary Explanation
Lab Report: 11.2.5 Manage Files Your Performance Your Score: 0 of 3 (0%) Pass Status: Not Passed Elapsed Time: 6 seconds Required Score: 100% Task Summary Actions you were required to perform: In Compress the D:\Graphics folderHide Details Set the Compressed attribute Apply the changes to all folders and files In Hide the D:\Finances folder In Set Read-only on filesHide Details Set read-only on 2017report.xlsx Set read-only on 2018report.xlsx Do not set read-only for the 2019report.xlsx file Explanation In this lab, your task is to complete the following: Compress the D:\Graphics folder and all of its contents. Hide the D:\Finances folder. Make the following files Read-only: D:\Finances\2017report.xlsx D:\Finances\2018report.xlsx Complete this lab as follows: 1. Compress a folder as follows: a. From the taskbar, open File Explorer. b. Maximize the window for easier viewing. c. In the left pane, expand This PC. d. Select Data (D:). e. Right-click Graphics and select Properties. f. On the General tab, select Advanced. g. Select Compress contents to save disk space. h. Click OK. i. Click OK. j. Make sure Apply changes to this folder, subfolders and files is selected. k. Click OK. 2. Hide a folder as follows: a. Right-click Finances and select Properties. b. Select Hidden. c. Click OK. 3. Set files to Read-only as follows: a. Double-click Finances to view its contents. b. Right-click 2017report.xlsx and select Properties. c. Select Read-only. d. Click OK. e. -
The Linux Command Line
The Linux Command Line Fifth Internet Edition William Shotts A LinuxCommand.org Book Copyright ©2008-2019, William E. Shotts, Jr. This work is licensed under the Creative Commons Attribution-Noncommercial-No De- rivative Works 3.0 United States License. To view a copy of this license, visit the link above or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042. A version of this book is also available in printed form, published by No Starch Press. Copies may be purchased wherever fine books are sold. No Starch Press also offers elec- tronic formats for popular e-readers. They can be reached at: https://www.nostarch.com. Linux® is the registered trademark of Linus Torvalds. All other trademarks belong to their respective owners. This book is part of the LinuxCommand.org project, a site for Linux education and advo- cacy devoted to helping users of legacy operating systems migrate into the future. You may contact the LinuxCommand.org project at http://linuxcommand.org. Release History Version Date Description 19.01A January 28, 2019 Fifth Internet Edition (Corrected TOC) 19.01 January 17, 2019 Fifth Internet Edition. 17.10 October 19, 2017 Fourth Internet Edition. 16.07 July 28, 2016 Third Internet Edition. 13.07 July 6, 2013 Second Internet Edition. 09.12 December 14, 2009 First Internet Edition. Table of Contents Introduction....................................................................................................xvi Why Use the Command Line?......................................................................................xvi -
Ardpower Documentation Release V1.2.0
ardPower Documentation Release v1.2.0 Anirban Roy Das Sep 27, 2017 Contents 1 Introduction 1 2 Screenshot 3 3 Documentaion 5 3.1 Overview.................................................5 3.2 Installation................................................7 3.3 Usage................................................... 12 4 Indices and tables 13 i ii CHAPTER 1 Introduction Its a custom Oh-My-Zsh Theme inspired by many custom themes suited for a perfect ZSH Environment under Byobu with Tmux Backend. 1 ardPower Documentation, Release v1.2.0 2 Chapter 1. Introduction 3 ardPower Documentation, Release v1.2.0 CHAPTER 2 Screenshot 4 Chapter 2. Screenshot CHAPTER 3 Documentaion You can also find PDF version of the documentation here. Overview We will start with understanding the individual components of an entire CLI. Generally we don’t put much attention to what we do. We just fire up a terminal or some say sheel and start typing our commands and get the result. That’s all. But there are a lot of things that goes behind all this. Terminal The very first component is the Terminal. So what is a Terminal? A terminal emulator, terminal application, term, or tty for short, is a program that emulates a video ter- minal within some other display architecture. Though typically synonymous with a shell or text terminal, the term terminal covers all remote terminals, including graphical interfaces. A terminal emulator inside a graphical user interface is often called a terminal window.A terminal window allows the user access to a text terminal and all its applications such as command-line interfaces (CLI) and text user interface (TUI) applications. -
NETSTAT Command
NETSTAT Command | NETSTAT Command | Use the NETSTAT command to display network status of the local host. | | ┌┐────────────── | 55──NETSTAT─────6─┤ Option ├─┴──┬────────────────────────────────── ┬ ─ ─ ─ ────────────────────────────────────────5% | │┌┐───────────────────── │ | └─(──SELect───6─┤ Select_String ├─┴ ─ ┘ | Option: | ┌┐─COnn────── (1, 2) ──────────────── | ├──┼─────────────────────────── ┼ ─ ──────────────────────────────────────────────────────────────────────────────┤ | ├─ALL───(2)──────────────────── ┤ | ├─ALLConn─────(1, 2) ────────────── ┤ | ├─ARp ipaddress───────────── ┤ | ├─CLients─────────────────── ┤ | ├─DEvlinks────────────────── ┤ | ├─Gate───(3)─────────────────── ┤ | ├─┬─Help─ ┬─ ───────────────── ┤ | │└┘─?──── │ | ├─HOme────────────────────── ┤ | │┌┐─2ð────── │ | ├─Interval─────(1, 2) ─┼───────── ┼─ ┤ | │└┘─seconds─ │ | ├─LEVel───────────────────── ┤ | ├─POOLsize────────────────── ┤ | ├─SOCKets─────────────────── ┤ | ├─TCp serverid───(1) ─────────── ┤ | ├─TELnet───(4)───────────────── ┤ | ├─Up──────────────────────── ┤ | └┘─┤ Command ├───(5)──────────── | Command: | ├──┬─CP cp_command───(6) ─ ┬ ────────────────────────────────────────────────────────────────────────────────────────┤ | ├─DELarp ipaddress─ ┤ | ├─DRop conn_num──── ┤ | └─RESETPool──────── ┘ | Select_String: | ├─ ─┬─ipaddress────(3) ┬ ─ ───────────────────────────────────────────────────────────────────────────────────────────┤ | ├─ldev_num─────(4) ┤ | └─userid────(2) ─── ┘ | Notes: | 1 Only ALLCON, CONN and TCP are valid with INTERVAL. | 2 The userid -
Operational Semantics with Hierarchical Abstract Syntax Graphs*
Operational Semantics with Hierarchical Abstract Syntax Graphs* Dan R. Ghica Huawei Research, Edinburgh University of Birmingham, UK This is a motivating tutorial introduction to a semantic analysis of programming languages using a graphical language as the representation of terms, and graph rewriting as a representation of reduc- tion rules. We show how the graphical language automatically incorporates desirable features, such as a-equivalence and how it can describe pure computation, imperative store, and control features in a uniform framework. The graph semantics combines some of the best features of structural oper- ational semantics and abstract machines, while offering powerful new methods for reasoning about contextual equivalence. All technical details are available in an extended technical report by Muroya and the author [11] and in Muroya’s doctoral dissertation [21]. 1 Hierarchical abstract syntax graphs Before proceeding with the business of analysing and transforming the source code of a program, a com- piler first parses the input text into a sequence of atoms, the lexemes, and then assembles them into a tree, the Abstract Syntax Tree (AST), which corresponds to its grammatical structure. The reason for preferring the AST to raw text or a sequence of lexemes is quite obvious. The structure of the AST incor- porates most of the information needed for the following stage of compilation, in particular identifying operations as nodes in the tree and operands as their branches. This makes the AST algorithmically well suited for its purpose. Conversely, the AST excludes irrelevant lexemes, such as separators (white-space, commas, semicolons) and aggregators (brackets, braces), by making them implicit in the tree-like struc- ture. -
Unix Systems: Shell Scripting (III)
Unix Systems: Shell Scripting (III) Bruce Beckles University of Cambridge Computing Service 1 Introduction • Who: ! Bruce Beckles, e-Science Specialist, UCS • What: ! Unix Systems: Shell Scripting (III) course ! Follows on from “Unix Systems: Shell Scripting (II)” ! Part of the Scientific Computing series of courses • Contact (questions, etc): ! [email protected] • Health & Safety, etc: ! Fire exits • Please switch off mobile phones! [email protected] Unix Systems: Shell Scripting (III) 2 As this course is part of the Scientific Computing series of courses run by the Computing Service, all the examples that we use will be more relevant to scientific computing than to system administration, etc. This does not mean that people who wish to learn shell scripting for system administration and other such tasks will get nothing from this course, as the techniques and underlying knowledge taught are applicable to shell scripts written for almost any purpose. However, such individuals should be aware that this course was not designed with them in mind. For details of the “Unix Systems: Shell Scripting (II)” course, see: http://www.cam.ac.uk/cs/courses/coursedesc/linux.html#script2 2 What we don’t cover • Different types of shell: ! We are using the Bourne-Again SHell (bash). • Differences between versions of bash • Very advanced shell scripting – try this course instead: ! “Programming: Python for Absolute Beginners” [email protected] Unix Systems: Shell Scripting (III) 3 bash is probably the most common shell on modern Unix/Linux systems – in fact, on most modern Linux distributions it will be the default shell (the shell users get if they don’t specify a different one). -
Programming Project #2 Due: Thursday, May 13Th, 2004, 11:59 Pm
CS155: Computer Security Spring 2004 Programming Project #2 Due: Thursday, May 13th, 2004, 11:59 pm 1 Introduction 1.1 Summary In this project, you will write Josh, the journaling operator shell. Josh is a setuid-root shell that allows users to undertake a subset of root’s capabilities. Your starting point is OSH, a minimal shell developed by Gunnar Ritter. You may work alone, or in pairs. You should not collaborate with others outside your group. You will use the Boxes system again. Remember to test your Josh in a closedbox. This as- signment specification is quite long, but much of it is intended to clarify points of confusion raised by previous years’ students. Please be sure to read it carefully before beginning to code. 1.2 The Problem As discussed in class, the classical Unix permissions model does not manage privilege delegation effectively. To perform routine administrative tasks (such as cleaning out the /tmp directory), one must possess the root password, and can therefore perform other, undesirable actions (such as reading users’ mail). This limitation manifests itself most acutely in large Unix installations, where there are typically many administrators tasked with various duties. Finer granularity of access is required for such systems, along with the ability to correctly log the important events for post-attack analysis. Various systems have been devised to overcome this limitation, and allow unprivileged users to un- dertake some subset of root’s capabilities. A commonly-used example is Sudo (http://www.sudo.ws/). We will take an approach more like that taken by OSH, the Operator Shell by Michael Neuman.