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Storage Administration Guide Storage Administration Guide SUSE Linux Enterprise Server 12 SP4
SUSE Linux Enterprise Server 12 SP4 Storage Administration Guide Storage Administration Guide SUSE Linux Enterprise Server 12 SP4 Provides information about how to manage storage devices on a SUSE Linux Enterprise Server. Publication Date: September 24, 2021 SUSE LLC 1800 South Novell Place Provo, UT 84606 USA https://documentation.suse.com Copyright © 2006– 2021 SUSE LLC and contributors. All rights reserved. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or (at your option) version 1.3; with the Invariant Section being this copyright notice and license. A copy of the license version 1.2 is included in the section entitled “GNU Free Documentation License”. For SUSE trademarks, see https://www.suse.com/company/legal/ . All other third-party trademarks are the property of their respective owners. Trademark symbols (®, ™ etc.) denote trademarks of SUSE and its aliates. Asterisks (*) denote third-party trademarks. All information found in this book has been compiled with utmost attention to detail. However, this does not guarantee complete accuracy. Neither SUSE LLC, its aliates, the authors nor the translators shall be held liable for possible errors or the consequences thereof. Contents About This Guide xii 1 Available Documentation xii 2 Giving Feedback xiv 3 Documentation Conventions xiv 4 Product Life Cycle and Support xvi Support Statement for SUSE Linux Enterprise Server xvii • Technology Previews xviii I FILE SYSTEMS AND MOUNTING 1 1 Overview -
Ubuntu Kung Fu
Prepared exclusively for Alison Tyler Download at Boykma.Com What readers are saying about Ubuntu Kung Fu Ubuntu Kung Fu is excellent. The tips are fun and the hope of discov- ering hidden gems makes it a worthwhile task. John Southern Former editor of Linux Magazine I enjoyed Ubuntu Kung Fu and learned some new things. I would rec- ommend this book—nice tips and a lot of fun to be had. Carthik Sharma Creator of the Ubuntu Blog (http://ubuntu.wordpress.com) Wow! There are some great tips here! I have used Ubuntu since April 2005, starting with version 5.04. I found much in this book to inspire me and to teach me, and it answered lingering questions I didn’t know I had. The book is a good resource that I will gladly recommend to both newcomers and veteran users. Matthew Helmke Administrator, Ubuntu Forums Ubuntu Kung Fu is a fantastic compendium of useful, uncommon Ubuntu knowledge. Eric Hewitt Consultant, LiveLogic, LLC Prepared exclusively for Alison Tyler Download at Boykma.Com Ubuntu Kung Fu Tips, Tricks, Hints, and Hacks Keir Thomas The Pragmatic Bookshelf Raleigh, North Carolina Dallas, Texas Prepared exclusively for Alison Tyler Download at Boykma.Com Many of the designations used by manufacturers and sellers to distinguish their prod- ucts are claimed as trademarks. Where those designations appear in this book, and The Pragmatic Programmers, LLC was aware of a trademark claim, the designations have been printed in initial capital letters or in all capitals. The Pragmatic Starter Kit, The Pragmatic Programmer, Pragmatic Programming, Pragmatic Bookshelf and the linking g device are trademarks of The Pragmatic Programmers, LLC. -
System Calls System Calls
System calls We will investigate several issues related to system calls. Read chapter 12 of the book Linux system call categories file management process management error handling note that these categories are loosely defined and much is behind included, e.g. communication. Why? 1 System calls File management system call hierarchy you may not see some topics as part of “file management”, e.g., sockets 2 System calls Process management system call hierarchy 3 System calls Error handling hierarchy 4 Error Handling Anything can fail! System calls are no exception Try to read a file that does not exist! Error number: errno every process contains a global variable errno errno is set to 0 when process is created when error occurs errno is set to a specific code associated with the error cause trying to open file that does not exist sets errno to 2 5 Error Handling error constants are defined in errno.h here are the first few of errno.h on OS X 10.6.4 #define EPERM 1 /* Operation not permitted */ #define ENOENT 2 /* No such file or directory */ #define ESRCH 3 /* No such process */ #define EINTR 4 /* Interrupted system call */ #define EIO 5 /* Input/output error */ #define ENXIO 6 /* Device not configured */ #define E2BIG 7 /* Argument list too long */ #define ENOEXEC 8 /* Exec format error */ #define EBADF 9 /* Bad file descriptor */ #define ECHILD 10 /* No child processes */ #define EDEADLK 11 /* Resource deadlock avoided */ 6 Error Handling common mistake for displaying errno from Linux errno man page: 7 Error Handling Description of the perror () system call. -
Open Source Projects As Incubators of Innovation
RESEARCH CONTRIBUTIONS TO ORGANIZATIONAL SOCIOLOGY AND INNOVATION STUDIES / STUTTGARTER BEITRÄGE ZUR ORGANISATIONS- UND INNOVATIONSSOZIOLOGIE SOI Discussion Paper 2017-03 Open Source Projects as Incubators of Innovation From Niche Phenomenon to Integral Part of the Software Industry Jan-Felix Schrape Institute for Social Sciences Organizational Sociology and Innovation Studies Jan-Felix Schrape Open Source Projects as Incubators of Innovation. From Niche Phenomenon to Integral Part of the Software Industry. SOI Discussion Paper 2017-03 University of Stuttgart Institute for Social Sciences Department of Organizational Sociology and Innovation Studies Seidenstr. 36 D-70174 Stuttgart Editor Prof. Dr. Ulrich Dolata Tel.: +49 711 / 685-81001 [email protected] Managing Editor Dr. Jan-Felix Schrape Tel.: +49 711 / 685-81004 [email protected] Research Contributions to Organizational Sociology and Innovation Studies Discussion Paper 2017-03 (May 2017) ISSN 2191-4990 © 2017 by the author(s) Jan-Felix Schrape is senior researcher at the Department of Organizational Sociology and Innovation Studies, University of Stuttgart (Germany). [email protected] Additional downloads from the Department of Organizational Sociology and Innovation Studies at the Institute for Social Sciences (University of Stuttgart) are filed under: http://www.uni-stuttgart.de/soz/oi/publikationen/ Abstract Over the last 20 years, open source development has become an integral part of the software industry and a key component of the innovation strategies of all major IT providers. Against this backdrop, this paper seeks to develop a systematic overview of open source communities and their socio-economic contexts. I begin with a recon- struction of the genesis of open source software projects and their changing relation- ships to established IT companies. -
File Handling in Python
hapter C File Handling in 2 Python There are many ways of trying to understand programs. People often rely too much on one way, which is called "debugging" and consists of running a partly- understood program to see if it does what you expected. Another way, which ML advocates, is to install some means of understanding in the very programs themselves. — Robin Milner In this Chapter » Introduction to Files » Types of Files » Opening and Closing a 2.1 INTRODUCTION TO FILES Text File We have so far created programs in Python that » Writing to a Text File accept the input, manipulate it and display the » Reading from a Text File output. But that output is available only during » Setting Offsets in a File execution of the program and input is to be entered through the keyboard. This is because the » Creating and Traversing a variables used in a program have a lifetime that Text File lasts till the time the program is under execution. » The Pickle Module What if we want to store the data that were input as well as the generated output permanently so that we can reuse it later? Usually, organisations would want to permanently store information about employees, inventory, sales, etc. to avoid repetitive tasks of entering the same data. Hence, data are stored permanently on secondary storage devices for reusability. We store Python programs written in script mode with a .py extension. Each program is stored on the secondary device as a file. Likewise, the data entered, and the output can be stored permanently into a file. -
System Calls and Standard I/O
System Calls and Standard I/O Professor Jennifer Rexford http://www.cs.princeton.edu/~jrex 1 Goals of Today’s Class • System calls o How a user process contacts the Operating System o For advanced services that may require special privilege • Standard I/O library o Generic I/O support for C programs o A smart wrapper around I/O-related system calls o Stream concept, line-by-line input, formatted output, ... 2 1 System Calls 3 Communicating With the OS User Process signals systems calls Operating System • System call o Request to the operating system to perform a task o … that the process does not have permission to perform • Signal o Asynchronous notification sent to a process … to notify the process of an event that has occurred o 4 2 Processor Modes • The OS must restrict what a user process can do o What instructions can execute o What portions of the address space are accessible • Supervisor mode (or kernel mode) o Can execute any instructions in the instruction set – Including halting the processor, changing mode bit, initiating I/O o Can access any memory location in the system – Including code and data in the OS address space • User mode o Restricted capabilities – Cannot execute privileged instructions – Cannot directly reference code or data in OS address space o Any such attempt results in a fatal “protection fault” – Instead, access OS code and data indirectly via system calls 5 Main Categories of System Calls • File system o Low-level file I/O o E.g., creat, open, read, write, lseek, close • Multi-tasking mechanisms o Process -
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. -
File Permissions Do Not Restrict Root
Filesystem Security 1 General Principles • Files and folders are managed • A file handle provides an by the operating system opaque identifier for a • Applications, including shells, file/folder access files through an API • File operations • Access control entry (ACE) – Open file: returns file handle – Allow/deny a certain type of – Read/write/execute file access to a file/folder by – Close file: invalidates file user/group handle • Access control list (ACL) • Hierarchical file organization – Collection of ACEs for a – Tree (Windows) file/folder – DAG (Linux) 2 Discretionary Access Control (DAC) • Users can protect what they own – The owner may grant access to others – The owner may define the type of access (read/write/execute) given to others • DAC is the standard model used in operating systems • Mandatory Access Control (MAC) – Alternative model not covered in this lecture – Multiple levels of security for users and documents – Read down and write up principles 3 Closed vs. Open Policy Closed policy Open Policy – Also called “default secure” • Deny Tom read access to “foo” • Give Tom read access to “foo” • Deny Bob r/w access to “bar” • Give Bob r/w access to “bar • Tom: I would like to read “foo” • Tom: I would like to read “foo” – Access denied – Access allowed • Tom: I would like to read “bar” • Tom: I would like to read “bar” – Access allowed – Access denied 4 Closed Policy with Negative Authorizations and Deny Priority • Give Tom r/w access to “bar” • Deny Tom write access to “bar” • Tom: I would like to read “bar” – Access -
Singularityce User Guide Release 3.8
SingularityCE User Guide Release 3.8 SingularityCE Project Contributors Aug 16, 2021 CONTENTS 1 Getting Started & Background Information3 1.1 Introduction to SingularityCE......................................3 1.2 Quick Start................................................5 1.3 Security in SingularityCE........................................ 15 2 Building Containers 19 2.1 Build a Container............................................. 19 2.2 Definition Files.............................................. 24 2.3 Build Environment............................................ 35 2.4 Support for Docker and OCI....................................... 39 2.5 Fakeroot feature............................................. 79 3 Signing & Encryption 83 3.1 Signing and Verifying Containers.................................... 83 3.2 Key commands.............................................. 88 3.3 Encrypted Containers.......................................... 90 4 Sharing & Online Services 95 4.1 Remote Endpoints............................................ 95 4.2 Cloud Library.............................................. 103 5 Advanced Usage 109 5.1 Bind Paths and Mounts.......................................... 109 5.2 Persistent Overlays............................................ 115 5.3 Running Services............................................. 118 5.4 Environment and Metadata........................................ 129 5.5 OCI Runtime Support.......................................... 140 5.6 Plugins................................................. -
Software Wars, Business Strategies and IP Litigation
Software Wars, Business Strategies and IP Litigation Immediately after Oracle America filed a patent infringement suit against Google Inc. in August 2010 the trade press labelled this a “software war.” Their interest was a trial featuring Oracle’s “star” counsel David Boies. In mid-January often cited Florian Mueller of NoSoftwarePatents, wrote “Google is patently too weak to protect Android—Google’s cell phone software.”1 (On April 4 Lead bidder Google offered $900 million for Nortel’s 6,000 patents and applications. A decision is expected in June}. By the end of March he had counted 39 patent infringement suits against Google.2 Whether Oracle wins Oracle v Google or not, Oracle and IBM may become losers. It is important that Oracle not alienate the software development community or its customers as it attempts to monetise the assets from the Sun Microsystems—now Oracle America— acquisition. The Oracle v. Google complaint was carefully targeted at Google’s Android software, avoiding the appearance of monetising the Java language and platform itself. The Android software was developed as open source in conjunction with the Open Handset Alliance. Android's mobile operating system is based on a modified version of the Linux kernel, subject to Linux patents. Google published all of the computer code under an Apache Software Foundation License.3 This license is royalty-free and places no restrictions on derivative products or commercial use. Based on IDC market share estimates by the fourth quarter of 2010, Android phones had 39% of the market. An Oracle asset gained through the acquisition of Sun was the OpenOffice open-source software—one of the only remaining substantial “competitors” to Microsoft’s document processing applications. -
60 External USB Hard Drive KNOW-HOW 60
KNOW-HOW Ask Klaus! ASK KLAUS! during unmounting, and lost data results I edit an existing script that already on a frequent basis when I disconnect comes with Fedora 7 (as used by the the device. desktop), to resolve the problem? Or is The drive heads are not stopped ei- this behavior compiled in? Klaus Knopper is the creator of ther, and a strange whirring chirp sound I believe the “eject” feature used by Knoppix and co-founder of the occurs when unplugging the drive while Gnome is only meant for flash memory the platters are still spinning. drives such as USB keys, where there is LinuxTag expo. He currently I searched Google and found a shell no concept of flushing the data in RAM script to properly unmount the drive, to the magnetic storage medium and works as a teacher, program- and it uses a tool called sdparm to sync stopping the heads, and hence it is a mer, and consultant. If you have and stop the drive heads before physi- rather simple solution for unmounting cally disconnecting the USB hard drive. I that is not suitable for external portable a configuration problem, or if did not have sdparm installed by default hard drives. from my Fedora 7 distribution (obtained Thanks in advance for considering this you just want to learn more through a Linux Magazine DVD) and Linux hardware challenge. about how Linux works, send had to search and install the tool myself using the package manager. (Zenity mes- The quite long script you sent your questions to: sage boxes also had to be installed for can be reduced to (more or less) this script.) this skeleton: klaus@linux-magazine. -
Provenance-Based Computing
UCAM-CL-TR-930 Technical Report ISSN 1476-2986 Number 930 Computer Laboratory Provenance-based computing Lucian Carata December 2018 15 JJ Thomson Avenue Cambridge CB3 0FD United Kingdom phone +44 1223 763500 https://www.cl.cam.ac.uk/ c 2018 Lucian Carata This technical report is based on a dissertation submitted July 2016 by the author for the degree of Doctor of Philosophy to the University of Cambridge, Wolfson College. Technical reports published by the University of Cambridge Computer Laboratory are freely available via the Internet: https://www.cl.cam.ac.uk/techreports/ ISSN 1476-2986 Provenance-based computing Lucian Carata Summary Relying on computing systems that become increasingly complex is difficult: with many factors potentially affecting the result of a computation or its properties, understanding where problems appear and fixing them is a challenging proposition. Typically, the process of finding solutions is driven by trial and error or by experience-based insights. In this dissertation, I examine the idea of using provenance metadata (the set of elements that have contributed to the existence of a piece of data, together with their relationships) instead. I show that considering provenance a primitive of computation enables the ex- ploration of system behaviour, targeting both retrospective analysis (root cause analysis, performance tuning) and hypothetical scenarios (what-if questions). In this context, prove- nance can be used as part of feedback loops, with a double purpose: building software that is able to adapt for meeting certain quality and performance targets (semi-automated tun- ing) and enabling human operators to exert high-level runtime control with limited previous knowledge of a system’s internal architecture.