The document discusses various Linux troubleshooting tools and techniques. It covers system monitoring tools like uptime, free, vmstat, and top that can help identify issues with system resources. It also discusses logging tools like syslog and application-specific logs that can provide error messages. Finally, it discusses diagnostic tools like ldd, strace, and procfs that can help troubleshoot configuration and code-level problems.
This document provides an overview of various Linux system troubleshooting tools and techniques. It discusses tools for checking system resources like memory and CPU usage (uptime, free, vmstat, top). It also covers tools for checking logs (/var/log, syslog, syslog.conf) and applications' own logs. Finally, it summarizes additional diagnostic tools like ldd, ldconfig, and ifconfig that can help troubleshoot issues.
This document lists and briefly describes the most commonly used AIX commands by the author. Some of the commands listed include acledit for changing access control lists, aclget for showing access control lists, alt_disk_install for installing an alternate root volume group, chdev for changing device parameters, chfs for changing file system sizes, cp for copying files, df for displaying disk space usage, and find to search for files and directories.
This document discusses the Linux kernel and kernel modules. It defines the kernel as representing the core of the operating system, including major components like the scheduler, memory manager, device drivers, and filesystems. It notes that the Linux kernel is modular, allowing functional blocks of software to be added or removed via modules. It then provides details on commands for working with modules like lsmod, rmmod, insmod, modprobe, and depmod. Finally, it briefly discusses kernel boot parameters and runtime parameters that can be modified using sysctl.
This document discusses Linux runlevels, shutdown, reboot, and changing runlevels. It explains that runlevels define the system state and tasks accomplished. The basic runlevels are 0 for halt, 1 for single-user mode, and 6 for reboot. Common multiuser runlevels are 2, 3, and 5. The telinit and init commands can be used to change runlevels without rebooting. The shutdown command sends warnings before switching runlevels and properly terminates processes. The /etc/inittab file determines the startup sequence by specifying actions like respawning processes.
This document discusses Linux runlevels, shutdown, reboot, and initialization scripts. It defines Linux runlevels for different system states including single-user mode. It describes how to change runlevels using telinit and init, and how to properly shutdown, reboot, or halt the system using commands like shutdown. The document also explains the role and format of the /etc/inittab file in determining the startup sequence and runlevels, as well as the initialization scripts run by init in different runlevels stored in directories like /etc/rc.d/rc?.d.
This document discusses Linux runlevels, shutdown, reboot, and changing runlevels. It explains that runlevels define the system state and tasks running. The default runlevel is set in /etc/inittab. Telinit and init can be used to change runlevels without rebooting. Shutdown sends warnings and signals processes to terminate cleanly before switching runlevels or powering off.
The document discusses Linux commands for redirecting standard input, output, and error streams. It covers commands like tee, xargs, <, >, >>, |, and backticks. Pipes and redirects allow commands to be chained together and output sent to files or other programs. Specific redirection examples are provided like redirecting just errors, appending output, and piping output between commands.
This document discusses Linux input/output redirection and piping commands. It covers redirecting standard input, output, and error to files or other programs. Specific redirection operators like >, >>, |, and < are explained along with examples. Commands like tee and xargs that are used to manage input/output streams are also overviewed. The key techniques covered include redirecting streams, piping outputs between commands, and using filters to process text streams.
This document provides an overview of various Linux system troubleshooting tools and techniques. It discusses tools for checking system resources like memory and CPU usage (uptime, free, vmstat, top). It also covers tools for checking logs (/var/log, syslog, syslog.conf) and applications' own logs. Finally, it summarizes additional diagnostic tools like ldd, ldconfig, and ifconfig that can help troubleshoot issues.
This document lists and briefly describes the most commonly used AIX commands by the author. Some of the commands listed include acledit for changing access control lists, aclget for showing access control lists, alt_disk_install for installing an alternate root volume group, chdev for changing device parameters, chfs for changing file system sizes, cp for copying files, df for displaying disk space usage, and find to search for files and directories.
This document discusses the Linux kernel and kernel modules. It defines the kernel as representing the core of the operating system, including major components like the scheduler, memory manager, device drivers, and filesystems. It notes that the Linux kernel is modular, allowing functional blocks of software to be added or removed via modules. It then provides details on commands for working with modules like lsmod, rmmod, insmod, modprobe, and depmod. Finally, it briefly discusses kernel boot parameters and runtime parameters that can be modified using sysctl.
This document discusses Linux runlevels, shutdown, reboot, and changing runlevels. It explains that runlevels define the system state and tasks accomplished. The basic runlevels are 0 for halt, 1 for single-user mode, and 6 for reboot. Common multiuser runlevels are 2, 3, and 5. The telinit and init commands can be used to change runlevels without rebooting. The shutdown command sends warnings before switching runlevels and properly terminates processes. The /etc/inittab file determines the startup sequence by specifying actions like respawning processes.
This document discusses Linux runlevels, shutdown, reboot, and initialization scripts. It defines Linux runlevels for different system states including single-user mode. It describes how to change runlevels using telinit and init, and how to properly shutdown, reboot, or halt the system using commands like shutdown. The document also explains the role and format of the /etc/inittab file in determining the startup sequence and runlevels, as well as the initialization scripts run by init in different runlevels stored in directories like /etc/rc.d/rc?.d.
This document discusses Linux runlevels, shutdown, reboot, and changing runlevels. It explains that runlevels define the system state and tasks running. The default runlevel is set in /etc/inittab. Telinit and init can be used to change runlevels without rebooting. Shutdown sends warnings and signals processes to terminate cleanly before switching runlevels or powering off.
The document discusses Linux commands for redirecting standard input, output, and error streams. It covers commands like tee, xargs, <, >, >>, |, and backticks. Pipes and redirects allow commands to be chained together and output sent to files or other programs. Specific redirection examples are provided like redirecting just errors, appending output, and piping output between commands.
This document discusses Linux input/output redirection and piping commands. It covers redirecting standard input, output, and error to files or other programs. Specific redirection operators like >, >>, |, and < are explained along with examples. Commands like tee and xargs that are used to manage input/output streams are also overviewed. The key techniques covered include redirecting streams, piping outputs between commands, and using filters to process text streams.
This document provides an overview of Linux kernel concepts, including key components like the scheduler and memory manager. It discusses how the kernel is modular and allows functional blocks to be added or removed via modules. It also covers commands like lsmod, rmmod, insmod, and modprobe for working with kernel modules, as well as kernel boot and runtime parameters that can be configured using sysctl.
This document discusses the Linux boot process from BIOS to kernel loading. It describes how the BIOS loads the master boot record from the boot disk, which then loads the boot loader like GRUB or LILO. The boot loader initializes the hardware and loads the kernel and initrd/root filesystem. The boot process and use of kernel parameters for booting into different modes or changing hardware settings are explained in detail with examples.
1. DPDK achieves high throughput packet processing on commodity hardware by reducing kernel overhead through techniques like polling, huge pages, and userspace drivers.
2. In Linux, packet processing involves expensive operations like system calls, interrupts, and data copying between kernel and userspace. DPDK avoids these by doing all packet processing in userspace.
3. DPDK uses techniques like isolating cores for packet I/O threads, lockless ring buffers, and NUMA awareness to further optimize performance. It can achieve throughput of over 14 million packets per second on 10GbE interfaces.
HKG18-TR14 - Postmortem Debugging with CoresightLinaro
Session ID: HKG18-TR14
Session Name: HKG18-TR14 - Postmortem Debugging with Coresight
Speaker: Leo Yan
Track: Training
★ Session Summary ★
For most cases we can easily debug with kernel's oops dumping info, but sometimes we need to know more information for program execution flow before the issue happens. So we can rely on two tracing methods to reproduce the program execution flow, one method is using software tracing which is kernel's pstore method; another method is to rely on Coresight hardware tracing, this method also can avoid extra workload introduced by tracing itself. Coresight has provided two mechanisms for Postmortem debugging, one method is Coresight CPU debug module so we can extract CPU program counter info, this is quite straightforward to debug CPU lockup issue; Another is Coresight panic kdump, we connect kernel kdump mechanism to extract Coresight tracing data so we can reproduce the last execution flow before panic (even hang issue with some tweaking in kernel). This session wants to go through these topics and demonstrate the debugging tools on 96boards Hikey in 25 minutes session.
---------------------------------------------------
★ Resources ★
Event Page: http://connect.linaro.org/resource/hkg18/hkg18-tr14/
Presentation: http://connect.linaro.org.s3.amazonaws.com/hkg18/presentations/hkg18-tr14.pdf
Video: http://connect.linaro.org.s3.amazonaws.com/hkg18/videos/hkg18-tr14.mp4
---------------------------------------------------
★ Event Details ★
Linaro Connect Hong Kong 2018 (HKG18)
19-23 March 2018
Regal Airport Hotel Hong Kong
---------------------------------------------------
Keyword: Training
'http://www.linaro.org'
'http://connect.linaro.org'
---------------------------------------------------
Follow us on Social Media
https://www.facebook.com/LinaroOrg
https://www.youtube.com/user/linaroorg?sub_confirmation=1
https://www.linkedin.com/company/1026961
Kernel Recipes 2015: Linux Kernel IO subsystem - How it works and how can I s...Anne Nicolas
Understanding how Linux kernel IO subsystem works is a key to analysis of a wide variety of issues occurring when running a Linux system. This talk is aimed at helping Linux users understand what is going on and how to get more insight into what is happening.
First we present an overview of Linux kernel block layer including different IO schedulers. We also talk about a new block multiqueue implementation that gets used for more and more devices.
After surveying the basic architecture we will be prepared to talk about tools to peek into it. We start with lightweight monitoring like iostat and continue with more heavy blktrace and variety of tools that are based on it. We demonstrate use of the tools on analysis of real world issues.
Jan Kara, SUSE
The document discusses Linux package management using RPM and YUM. It covers how to install, upgrade, remove packages and query the RPM database. Key topics include using RPM to install, upgrade, remove packages; checking package integrity with signatures; and querying the RPM database to list installed packages, files in a package, or which package installed a specific file.
101 3.5 create, monitor and kill processes v2Acácio Oliveira
This document discusses processes in Linux systems. It defines what a process is and lists key process attributes like PID, PPID, UID/GID, command, start time, state etc. It describes how to run jobs in the foreground and background, and send signals to processes. Commands to create, monitor and kill processes are covered, including ps, top, jobs, fg, bg and kill. Process states like running, stopped, sleeping and zombie are also defined.
The document provides information on RPM and YUM package management in Linux systems. It discusses key topics such as installing, upgrading, querying, and removing packages using RPM and YUM. Specific utilities like rpm, yum, and yumdownloader are also covered. The document also explains RPM concepts like packages, databases, and validating package integrity with GnuPG/PGP.
This document discusses processes in Linux systems. It defines what a process is and lists some key process attributes like PID, PPID, UID/GID, command, start time, and state. It describes how to create, monitor, and kill processes using commands like ps, top, jobs, fg, bg, and kill. It also covers running jobs in the foreground and background, signaling processes, and process states. Signals are discussed as the primary means of communication between processes.
The document discusses Linux/Unix interview questions and answers. It covers topics such as the GRUB bootloader, the Linux boot process, user profile files, changing the default runlevel, displaying user information with the finger command, inode numbers, increasing disk read performance, password expiration times, locking user passwords, default shells, user attributes defined in /etc/login.defs, changing the system's authentication method, modifying file attributes with chattr, network interface configuration files, changing network interface settings, the DNS configuration file, exporting NFS directories, checking open ports, soft vs hard links, setting expired passwords, restricting file insertion, displaying or killing processes accessing files/folders, killing all processes for a user, daily system analysis reports
This document discusses maintaining the integrity of Linux filesystems. It covers tools like fsck, e2fsck, tune2fs, and debugfs for checking and repairing filesystems. It also covers commands like df, du, and dumpe2fs for monitoring filesystem usage and properties. The document provides examples of using these tools to check filesystem integrity, find free space, view inode information, and explore filesystem internals.
This document discusses managing users and groups in Red Hat Linux 7. It explains that there are three types of users: the root superuser, normal custom users created by administrators, and system users created by packages. It describes the main files and commands used to create and manage users, including /etc/passwd, /etc/shadow, /etc/group, useradd, groupadd, and usermod. The default permissions and umask value are also covered.
Kernel Recipes 2014 - The Linux Kernel, how fast it is developed and how we s...Anne Nicolas
This talk will go into the latest statistics for the development of the Linux kernel.
It will describe how the many thousand developers all work together and are able to release a stable kernel every 3 months with no planning.
Greg Kroah-Hartman, Linux Foundation
This document discusses Linux file systems and partitioning. It covers commands used to create partitions like fdisk and mkfs, as well as filesystem types like ext3. It also discusses creating and managing swap spaces. The key points are that Linux uses mkfs to format partitions, fdisk to create partitions, and mkswap to initialize swap spaces which are then activated with swapon.
IRQs: the Hard, the Soft, the Threaded and the PreemptibleAlison Chaiken
The Linux kernel supports a diverse set of interrupt handlers that partition work into immediate and deferred tasks. The talk introduces the major varieties and explains how IRQs differ in the real-time kernel.
Kernel Recipes 2015: Kernel packet capture technologiesAnne Nicolas
Sniffing through the ages
Capturing packets running on the wire to send them to a software doing analysis seems at first sight a simple tasks. But one has not to forget that with current network this can means capturing 30M packets per second. The objective of this talk is to show what methods and techniques have been implemented in Linux and how they have evolved over time.
The talk will cover AF_PACKET capture as well as PF_RING, dpdk and netmap. It will try to show how the various evolution of hardware and software have had an impact on the design of these technologies. Regarding software a special focus will be made on Suricata IDS which is implementing most of these capture methods.
Eric Leblond, Stamus Networks
The document summarizes key concepts about operating system structures. It describes the services operating systems provide to users and processes, including user interfaces, program execution, I/O operations, file manipulation, communications, error detection, and resource allocation. It also discusses system call interfaces, common system calls, system programs, approaches to operating system design like layered and modular structures, virtual machines, operating system generation, and the system boot process.
The document provides an overview of the topics to be covered in the Linux Internals training course on Day 1. It will cover Linux architecture, kernel mode vs user mode, the Linux directory structure, file types and permissions, shell basics, the vi editor, and shell scripting. It also discusses the history and development of Linux, its key properties like multitasking and security, and the overall Linux system architecture including hardware controllers, the kernel, OS services, and user applications.
The document discusses Baidu's implementation of a private cloud platform based on CloudFoundry, including reforms made to support Java and C/C++ applications, standardizing processes, and future plans. It describes practices around automating operations, unifying standards, and linking the platform to other systems through components like file persistence and monitoring. Key reforms involved adapting CloudFoundry to CentOS, enhancing health monitoring, and supporting features like RPC and JMX access.
Log files - Approcci al TroubleshootingFulvio Corno
Master: Amministratore Linux - Livello Base
Nel contesto della formazione professionale rivolta ad aziende ed enti pubblici, sono stati preparati ed erogati dei corsi di Amministratore di sistemi Linux, al livello base ed al livello avanzato.
Il contenuto del corso è allineato con alcuni moduli della certificazione LPIC (Linux Professional Institute Certification), a cavallo tra i livelli 1 e 2. Tutto il materiale didattico è disponibile liberamente con licenza Creative Commons BY-NC-SA.
I docenti del corso sono i proff. Giovanni Squillero, Bartolomeo Montrucchio e Fulvio Corno.
Maggiori informazioni: http://elite.polito.it/index.php/teaching/current-courses/255-master-linux-admin
Gace Basic Computer Operation And TroubleshootingNisa Peek
This document provides an introduction to basic computer hardware, components, cabling, and troubleshooting. It lists common computer parts like the power switch, hard drive, floppy disk drive, CD/DVD drive, serial ports, parallel port, USB port, keyboard, mouse, network card, modem, sound card, and video card. It also mentions the motherboard, RAM, cables, and power cord. The document provides storage capacities for floppy disks, zip cartridges, CDs, and DVDs. It stresses the importance of backups and having updated anti-virus software and security patches. It lists some common troubleshooting steps and provides additional educational technology resources.
This document provides an overview of troubleshooting TCP/IP networks using Linux tools. It discusses both reactive troubleshooting to identify errors and proactive troubleshooting to identify performance issues. For reactive troubleshooting, it breaks it down by protocol (Ethernet/ARP, IP/ICMP, TCP/UDP, applications) and provides example tools and case studies for each. For proactive troubleshooting, it focuses on examining the entire network for factors affecting performance, using tools like netperf and iptraf. The document assumes a basic TCP/IP and Linux knowledge and provides a review of the TCP/IP protocol stack to set the stage for troubleshooting.
This document provides an overview of Linux kernel concepts, including key components like the scheduler and memory manager. It discusses how the kernel is modular and allows functional blocks to be added or removed via modules. It also covers commands like lsmod, rmmod, insmod, and modprobe for working with kernel modules, as well as kernel boot and runtime parameters that can be configured using sysctl.
This document discusses the Linux boot process from BIOS to kernel loading. It describes how the BIOS loads the master boot record from the boot disk, which then loads the boot loader like GRUB or LILO. The boot loader initializes the hardware and loads the kernel and initrd/root filesystem. The boot process and use of kernel parameters for booting into different modes or changing hardware settings are explained in detail with examples.
1. DPDK achieves high throughput packet processing on commodity hardware by reducing kernel overhead through techniques like polling, huge pages, and userspace drivers.
2. In Linux, packet processing involves expensive operations like system calls, interrupts, and data copying between kernel and userspace. DPDK avoids these by doing all packet processing in userspace.
3. DPDK uses techniques like isolating cores for packet I/O threads, lockless ring buffers, and NUMA awareness to further optimize performance. It can achieve throughput of over 14 million packets per second on 10GbE interfaces.
HKG18-TR14 - Postmortem Debugging with CoresightLinaro
Session ID: HKG18-TR14
Session Name: HKG18-TR14 - Postmortem Debugging with Coresight
Speaker: Leo Yan
Track: Training
★ Session Summary ★
For most cases we can easily debug with kernel's oops dumping info, but sometimes we need to know more information for program execution flow before the issue happens. So we can rely on two tracing methods to reproduce the program execution flow, one method is using software tracing which is kernel's pstore method; another method is to rely on Coresight hardware tracing, this method also can avoid extra workload introduced by tracing itself. Coresight has provided two mechanisms for Postmortem debugging, one method is Coresight CPU debug module so we can extract CPU program counter info, this is quite straightforward to debug CPU lockup issue; Another is Coresight panic kdump, we connect kernel kdump mechanism to extract Coresight tracing data so we can reproduce the last execution flow before panic (even hang issue with some tweaking in kernel). This session wants to go through these topics and demonstrate the debugging tools on 96boards Hikey in 25 minutes session.
---------------------------------------------------
★ Resources ★
Event Page: http://connect.linaro.org/resource/hkg18/hkg18-tr14/
Presentation: http://connect.linaro.org.s3.amazonaws.com/hkg18/presentations/hkg18-tr14.pdf
Video: http://connect.linaro.org.s3.amazonaws.com/hkg18/videos/hkg18-tr14.mp4
---------------------------------------------------
★ Event Details ★
Linaro Connect Hong Kong 2018 (HKG18)
19-23 March 2018
Regal Airport Hotel Hong Kong
---------------------------------------------------
Keyword: Training
'http://www.linaro.org'
'http://connect.linaro.org'
---------------------------------------------------
Follow us on Social Media
https://www.facebook.com/LinaroOrg
https://www.youtube.com/user/linaroorg?sub_confirmation=1
https://www.linkedin.com/company/1026961
Kernel Recipes 2015: Linux Kernel IO subsystem - How it works and how can I s...Anne Nicolas
Understanding how Linux kernel IO subsystem works is a key to analysis of a wide variety of issues occurring when running a Linux system. This talk is aimed at helping Linux users understand what is going on and how to get more insight into what is happening.
First we present an overview of Linux kernel block layer including different IO schedulers. We also talk about a new block multiqueue implementation that gets used for more and more devices.
After surveying the basic architecture we will be prepared to talk about tools to peek into it. We start with lightweight monitoring like iostat and continue with more heavy blktrace and variety of tools that are based on it. We demonstrate use of the tools on analysis of real world issues.
Jan Kara, SUSE
The document discusses Linux package management using RPM and YUM. It covers how to install, upgrade, remove packages and query the RPM database. Key topics include using RPM to install, upgrade, remove packages; checking package integrity with signatures; and querying the RPM database to list installed packages, files in a package, or which package installed a specific file.
101 3.5 create, monitor and kill processes v2Acácio Oliveira
This document discusses processes in Linux systems. It defines what a process is and lists key process attributes like PID, PPID, UID/GID, command, start time, state etc. It describes how to run jobs in the foreground and background, and send signals to processes. Commands to create, monitor and kill processes are covered, including ps, top, jobs, fg, bg and kill. Process states like running, stopped, sleeping and zombie are also defined.
The document provides information on RPM and YUM package management in Linux systems. It discusses key topics such as installing, upgrading, querying, and removing packages using RPM and YUM. Specific utilities like rpm, yum, and yumdownloader are also covered. The document also explains RPM concepts like packages, databases, and validating package integrity with GnuPG/PGP.
This document discusses processes in Linux systems. It defines what a process is and lists some key process attributes like PID, PPID, UID/GID, command, start time, and state. It describes how to create, monitor, and kill processes using commands like ps, top, jobs, fg, bg, and kill. It also covers running jobs in the foreground and background, signaling processes, and process states. Signals are discussed as the primary means of communication between processes.
The document discusses Linux/Unix interview questions and answers. It covers topics such as the GRUB bootloader, the Linux boot process, user profile files, changing the default runlevel, displaying user information with the finger command, inode numbers, increasing disk read performance, password expiration times, locking user passwords, default shells, user attributes defined in /etc/login.defs, changing the system's authentication method, modifying file attributes with chattr, network interface configuration files, changing network interface settings, the DNS configuration file, exporting NFS directories, checking open ports, soft vs hard links, setting expired passwords, restricting file insertion, displaying or killing processes accessing files/folders, killing all processes for a user, daily system analysis reports
This document discusses maintaining the integrity of Linux filesystems. It covers tools like fsck, e2fsck, tune2fs, and debugfs for checking and repairing filesystems. It also covers commands like df, du, and dumpe2fs for monitoring filesystem usage and properties. The document provides examples of using these tools to check filesystem integrity, find free space, view inode information, and explore filesystem internals.
This document discusses managing users and groups in Red Hat Linux 7. It explains that there are three types of users: the root superuser, normal custom users created by administrators, and system users created by packages. It describes the main files and commands used to create and manage users, including /etc/passwd, /etc/shadow, /etc/group, useradd, groupadd, and usermod. The default permissions and umask value are also covered.
Kernel Recipes 2014 - The Linux Kernel, how fast it is developed and how we s...Anne Nicolas
This talk will go into the latest statistics for the development of the Linux kernel.
It will describe how the many thousand developers all work together and are able to release a stable kernel every 3 months with no planning.
Greg Kroah-Hartman, Linux Foundation
This document discusses Linux file systems and partitioning. It covers commands used to create partitions like fdisk and mkfs, as well as filesystem types like ext3. It also discusses creating and managing swap spaces. The key points are that Linux uses mkfs to format partitions, fdisk to create partitions, and mkswap to initialize swap spaces which are then activated with swapon.
IRQs: the Hard, the Soft, the Threaded and the PreemptibleAlison Chaiken
The Linux kernel supports a diverse set of interrupt handlers that partition work into immediate and deferred tasks. The talk introduces the major varieties and explains how IRQs differ in the real-time kernel.
Kernel Recipes 2015: Kernel packet capture technologiesAnne Nicolas
Sniffing through the ages
Capturing packets running on the wire to send them to a software doing analysis seems at first sight a simple tasks. But one has not to forget that with current network this can means capturing 30M packets per second. The objective of this talk is to show what methods and techniques have been implemented in Linux and how they have evolved over time.
The talk will cover AF_PACKET capture as well as PF_RING, dpdk and netmap. It will try to show how the various evolution of hardware and software have had an impact on the design of these technologies. Regarding software a special focus will be made on Suricata IDS which is implementing most of these capture methods.
Eric Leblond, Stamus Networks
The document summarizes key concepts about operating system structures. It describes the services operating systems provide to users and processes, including user interfaces, program execution, I/O operations, file manipulation, communications, error detection, and resource allocation. It also discusses system call interfaces, common system calls, system programs, approaches to operating system design like layered and modular structures, virtual machines, operating system generation, and the system boot process.
The document provides an overview of the topics to be covered in the Linux Internals training course on Day 1. It will cover Linux architecture, kernel mode vs user mode, the Linux directory structure, file types and permissions, shell basics, the vi editor, and shell scripting. It also discusses the history and development of Linux, its key properties like multitasking and security, and the overall Linux system architecture including hardware controllers, the kernel, OS services, and user applications.
The document discusses Baidu's implementation of a private cloud platform based on CloudFoundry, including reforms made to support Java and C/C++ applications, standardizing processes, and future plans. It describes practices around automating operations, unifying standards, and linking the platform to other systems through components like file persistence and monitoring. Key reforms involved adapting CloudFoundry to CentOS, enhancing health monitoring, and supporting features like RPC and JMX access.
Log files - Approcci al TroubleshootingFulvio Corno
Master: Amministratore Linux - Livello Base
Nel contesto della formazione professionale rivolta ad aziende ed enti pubblici, sono stati preparati ed erogati dei corsi di Amministratore di sistemi Linux, al livello base ed al livello avanzato.
Il contenuto del corso è allineato con alcuni moduli della certificazione LPIC (Linux Professional Institute Certification), a cavallo tra i livelli 1 e 2. Tutto il materiale didattico è disponibile liberamente con licenza Creative Commons BY-NC-SA.
I docenti del corso sono i proff. Giovanni Squillero, Bartolomeo Montrucchio e Fulvio Corno.
Maggiori informazioni: http://elite.polito.it/index.php/teaching/current-courses/255-master-linux-admin
Gace Basic Computer Operation And TroubleshootingNisa Peek
This document provides an introduction to basic computer hardware, components, cabling, and troubleshooting. It lists common computer parts like the power switch, hard drive, floppy disk drive, CD/DVD drive, serial ports, parallel port, USB port, keyboard, mouse, network card, modem, sound card, and video card. It also mentions the motherboard, RAM, cables, and power cord. The document provides storage capacities for floppy disks, zip cartridges, CDs, and DVDs. It stresses the importance of backups and having updated anti-virus software and security patches. It lists some common troubleshooting steps and provides additional educational technology resources.
This document provides an overview of troubleshooting TCP/IP networks using Linux tools. It discusses both reactive troubleshooting to identify errors and proactive troubleshooting to identify performance issues. For reactive troubleshooting, it breaks it down by protocol (Ethernet/ARP, IP/ICMP, TCP/UDP, applications) and provides example tools and case studies for each. For proactive troubleshooting, it focuses on examining the entire network for factors affecting performance, using tools like netperf and iptraf. The document assumes a basic TCP/IP and Linux knowledge and provides a review of the TCP/IP protocol stack to set the stage for troubleshooting.
The Gurubox Project: Open Source Troubleshooting ToolsWes Morgan
The document discusses IBM's Gurubox Project, which aims to provide a standardized set of open source troubleshooting tools for enterprise use. It describes the origins and goals of the project in addressing security and customization concerns when troubleshooting on customer networks. The bulk of the document then lists and briefly describes various open source networking, system, and web analysis tools that are included in the Gurubox toolkit for troubleshooting purposes.
Dokumen tersebut membahas tentang kuliah pengantar open source dan aplikasi Linux, mencakup tujuan dan topik kuliah seperti instalasi Linux dan pemecahan masalah dasar, serta langkah-langkah persiapan dan proses instalasi Linux.
Advanced performance troubleshooting using esxtopAlan Renouf
This document discusses using esxtop and resxtop tools to troubleshoot performance issues on VMware ESXi hosts. It provides 10 key things to know about esxtop counters and how they work. It then gives examples of using esxtop to troubleshoot common problems like CPU contention, memory issues, network throughput problems, and disk I/O latency. It also lists some other diagnostic tools that can be used along with esxtop.
As presented at LinuxCon, August 22nd 2014:
As the standardized offerings for infrastructure and cloud providers become more complex and interdependent, so too do the requirements to properly manage and troubleshoot them. The ability for technical teams to quickly localize bottlenecks, capacity limits, application issues, and other problems is now a key factor for a provider’s success. Whereas troubleshooting was considered a soft skill in the past, hosters must acknowledge and nourish the importance of this ability.
This session will present background information, case studies of specific events, and recommendations for improving root cause analysis of common complex managed hosting environment issues. The talk will draw upon experience of Webair’s own infrastructure and customer configurations, including complex environments with multiple layers of services.
The document provides guidance on troubleshooting Linux systems. It discusses preparing for troubleshooting by backing up data and documentation. When issues arise, it recommends gathering information from logs, researching if the problem is widespread, and considering likely causes such as user error, software/hardware issues, or network problems. It then offers solutions such as software and hardware remedies, and provides tips for troubleshooting specific components like applications, networks, disks, and packages.
This course covers the basics of Linux system administration over 15-20 hours, teaching students how to use the command line, configure networks and disks, manage users and software, monitor performance, backup systems, and troubleshoot issues. The course outline details lessons on topics like file systems, shells, vi editor, processes, packages, networking, and booting to provide students with foundational skills for administering Linux systems. The goal is for students to learn how to use and manage key components of Linux from the command line as a system administrator.
This document outlines the agenda and content for a Red Hat Certified Engineer course. The course is divided into three levels (first, second, third) that prepare students with increasing skills in Linux and system administration. The first level teaches Linux basics and commands for new users. The second level focuses on system administration skills. The third level covers networking, security administration, and configuring network services on a Red Hat server. Each level includes objectives, prerequisites, and descriptions of the skills that will be developed.
This document discusses managing disk quotas in Linux. It provides an overview of key commands used to set up, edit, check, generate reports on, and manage disk quotas, including quota, edquota, repquota, quotaon, and quotaoff. It describes how these commands work and their various options. The goal of disk quotas is to limit disk usage on a per-user or per-group basis to control storage consumption.
This document discusses managing disk quotas in Linux. It provides an overview of key commands used to set up, edit, check, generate reports on, and manage disk quotas, including quota, edquota, repquota, quotaon, and quotaoff. It describes how these commands work and their various options. The goal of disk quotas is to limit disk usage on a per-user or per-group basis to control storage consumption.
This document discusses managing disk quotas in Linux. It describes using the quota utility to view quota information, edquota to edit quotas, and repquota to generate reports. It also covers enabling and disabling quotas with quotaon and quotaoff. Key tools covered are quota, edquota, repquota, quotaon, and quotaoff. The document provides examples of using these tools to set user and group quotas, view quota usage, and manage quotas on Linux file systems.
This document discusses Linux performance tuning. It covers collecting meaningful benchmarks by establishing a baseline and running tests multiple times under consistent conditions. It also discusses several tools for benchmarking components like the CPU, disk, memory, and filesystem, such as hdparm, compiling software, lmbench, and iozone. Finally, it lists some performance tricks like disabling access times, binding processes to CPUs, tuning memory, using RAID, and disabling SELinux.
101 4.2 maintain the integrity of filesystemsAcácio Oliveira
The document discusses maintaining the integrity of Linux filesystems. It describes tools like fsck, e2fsck, and tune2fs for checking and repairing filesystems, as well as df, du, and debugfs for monitoring filesystem usage and exploring ext filesystem internals. The document provides examples of using these tools to check filesystems by label, UUID, or device node; view free space and inode information; and attempt undeletion of files.
101 4.2 maintain the integrity of filesystemsAcácio Oliveira
The document discusses maintaining the integrity of Linux filesystems. It describes tools like fsck, e2fsck, and tune2fs for checking filesystems, df and du for monitoring free space and disk usage. It provides examples of using these tools to check filesystems by label, UUID, or device name, and monitor mounted filesystem types and inodes. The document emphasizes that filesystems should be unmounted before running fsck to avoid potential damage.
This document discusses Linux system performance tuning. It defines benchmarks as repeatable performance measurements taken under consistent conditions. It provides examples of common benchmarking tools like hdparm, compiling software, lmbench, and iozone. It also discusses establishing baselines, collecting benchmarks in single-user mode, and averaging results. Finally, it lists some performance tricks like disabling atime, binding processes to CPUs, tuning memory and swap, implementing RAID, and disabling SELinux.
This document discusses system administration topics related to hardware configuration in Linux systems. It covers key areas like enabling and disabling peripherals, different storage devices, and hardware identification. It also describes hardware components like buses, ports, interrupts (IRQs), and direct memory access (DMA). Specific files like /proc/ioports, /proc/interrupts, and /proc/pci are discussed that provide information on the system's hardware configuration. Tools like lspci are also covered that can be used to view devices connected via the PCI bus.
This document summarizes a meeting of the Portuguese SharePoint Community held on June 12, 2010. The agenda included an overview of debugging, debugging tools, and next steps. It defines debugging as methodically finding and reducing bugs to make a program or hardware behave as expected. It discusses various debugging techniques like screen dumps, logs, code debugging in Visual Studio, web debugging with tools like Fiddler, and runtime debugging using the Windows kernel and tools like Windbg. Further reading materials are also provided.
The document provides an introduction to operating systems and real-time operating systems (RTOS). It defines an operating system as software that manages computer resources and provides common services for programs. An RTOS is designed for systems where response time is critical. The document discusses the components, features and types of both operating systems and RTOS, including examples like VxWorks and QNX.
This document provides information about operating systems and computer hardware concepts for a second year computer science course. It includes definitions of terms like 32-bit microprocessor, opcode, data bus, and cache memory. It also lists some common operating systems and describes concepts like multicore processors, virtualization, virtual memory, and the different states a process can be in.
The document discusses Process Control Daemon (PCD), an open source process manager for embedded Linux platforms. PCD aims to improve over traditional shell script-based startup by allowing deterministic, parallel startup and recovery actions for processes. It provides a centralized way to define and manage processes and their dependencies. Key features include event-driven startup, crash handling and logging, and a process API. PCD has modest resource needs and supports various architectures. It has benefited products by improving startup time, robustness, and debug capabilities.
These slides were presented during technical event at my organization. It focuses on overview to find a root cause of the unexpected system down events. It is mainly useful for Linux or Unix system administrators. Here, I tried to cover all aspects of the topic. It took me more than 2 hours to present these slides, but one can also cover these slides within short time-span. Gray background of slides is implemented to hide the company logo and to preserve the confidentially of private template. However, The Knowledge is not restricted :)
This document provides an overview of core Linux concepts related to hardware configuration and system administration. It covers key areas like enabling and disabling peripherals, different storage device types, hardware IDs and settings. It also defines terms like BIOS, buses, ports, interrupts and DMA channels that are used to interface hardware devices with the CPU. Specific commands to view hardware information are also outlined, such as lspci and examining files in the /proc directory.
The document discusses SUMA, a tool that automates the download of maintenance and technology levels from a fix server on AIX systems. It provides examples of using SUMA to list configuration settings, schedule periodic downloads of the latest fixes, and download specific fixes like APARs or filesets. SUMA allows flexibility in configuring fix types, actions, scheduling, logging and generating reports for download tasks.
The document discusses reformatting and installing Windows 7. It defines reformatting as erasing all information on a drive by formatting it to prepare for new data. It describes Windows 7 as a personal computer operating system released in 2009 that was praised as a major improvement over Windows Vista. It also defines an ISO image as a disk image file containing everything that would be written to an optical disc, sector by sector, and explains that ISO stands for International Organization for Standardization.
Bishwambar Sahoo is a Linux system administrator seeking a new position. He has 3.7 years of experience administering Red Hat Enterprise Linux systems. Currently he works as a technician at iYogi Technical Service Pvt. Ltd, where his responsibilities include monitoring systems, performing backups, managing user accounts, and troubleshooting issues. He has experience installing and configuring Linux servers, networking, security, and various applications like Apache, Nagios, and Samba.
This document discusses the Linux boot process, including:
1) The boot sequence starts with the BIOS initializing and loading the boot loader like GRUB or LILO.
2) The boot loader loads the Linux kernel and initiates the kernel initialization process.
3) Once loaded, the kernel mounts the root file system and launches the init process to start system services and bring the system to the desired run level.
This document provides an overview of IBM BPM problem determination and troubleshooting. It discusses the key databases used by IBM BPM, runtime and administration flows, clustered application servers, log files and locations. It also covers techniques for problem analysis including reviewing log files, checking product versions, and searching support resources. Tuning considerations and best practices for problem prevention are also outlined.
Similar to 101 apend. troubleshooting tools v2 (20)
This document discusses the differences between vulnerability scanning and penetration testing. Vulnerability scanning uses automated tools to identify vulnerabilities while penetration testing involves manual techniques to simulate real-world attacks. The document also notes that vulnerability scanning and penetration testing have different levels of testing and are covered in Topic 24 of the Security+ Study Guide for 10 minutes.
This document discusses application security controls and techniques. It covers secure coding concepts, other security controls and techniques, and provides a 10 minute overview of application security controls and techniques as outlined in the CompTIA Security+ Study Guide. The document was prepared by Acácio Oliveira in 2021.
This document discusses types of application attacks and is divided into two sections. The first section defines application attacks and covers common types. The second section explains the goals of application attacks and how they can divulge weaknesses in some applications. The entire document is part of a Security+ study guide and covers types of application attacks over a period of 20 minutes.
Security+ Lesson 01 Topic 19 - Summary of Social Engineering Attacks.pptxAcácio Oliveira
This document provides a summary of social engineering attacks. Social engineering attacks are effective because they target human nature. There are different types of social engineering attacks, such as pretexting where attackers pretend to be someone trustworthy to get victims to reveal sensitive information. The document is part of a study guide for the CompTIA Security+ certification and focuses on summarizing social engineering attacks.
This document discusses security assessment tools, including types of security assessments and specific assessment tools. It is part of a CompTIA Security+ study guide prepared in 2021, focusing on an overview of security assessment tools in about 10 minutes.
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This document discusses risk management best practices for the CompTIA Security+ exam, covering business continuity concepts, fault tolerance, and is part of a study guide prepared by Acácio Oliveira in 2021 with an estimated reading time of 10 minutes.
This document discusses physical security and environmental controls, which are important concepts for the CompTIA Security+ exam. It covers control types for physical security and the environment, such as restricting physical access and monitoring for issues like fires, floods or power outages. The document is from a study guide prepared in 2021 to help study for the Security+ exam.
This document discusses disaster recovery concepts for the CompTIA Security+ exam, including maintaining disaster recovery sites, performing regular data backups, and ensuring the ability to recover data and systems in the event of a disaster within 10 minutes of scheduled content.
This document discusses wireless security considerations for the CompTIA Security+ exam. It covers the unique security challenges of wireless networks compared to wired networks. Specific topics include security for wireless networks and an index of study guide topics related to wireless security considerations with an allocated time of 10 minutes.
Security+ Lesson 01 Topic 04 - Secure Network Design Elements and Components....Acácio Oliveira
This document discusses secure network design elements and components. It covers defense in depth as a strategy as well as elements and components of network design such as firewalls, intrusion detection systems, and virtual private networks. The document is from Acácio Oliveira's 2021 CompTIA Security+ Study Guide and focuses on secure network design for 10 minutes.
This document provides a 3-topic outline for a CompTIA Security+ study guide prepared by Acácio Oliveira in 2021. Topic 1 discusses secure network administration concepts like spam filters and network devices. Topic 2 is titled "Secure Network Administration Concepts" and is allocated 10 minutes of study time. The document also includes a topics index for the study guide.
This document provides an overview of the concepts to be covered in Lesson 01 on introduction to network devices from the CompTIA Security+ Study Guide. The lesson will be divided into three parts covering OSI models, basic network devices and layer security concepts in part 1; network devices in part 2; and spam filters and additional network devices in part 3, for a total time of 30 minutes.
Security+ Lesson 01 Topic 08 - Integrating Data and Systems with Third Partie...Acácio Oliveira
This document discusses integrating data and systems with third parties. It examines evaluating risks with integration and considerations for integration. The document is part of a Security+ study guide prepared by Acácio Oliveira in 2021 on the topic of integrating data and systems with third parties.
Security+ Lesson 01 Topic 07 - Risk Related Concepts.pptxAcácio Oliveira
This document outlines concepts related to risk for the CompTIA Security+ certification. It covers three topics on risk-related concepts over 30 minutes: policies for controlling and reducing risk, qualitative versus quantitative risk assessments, and treating risks such as those involving cloud computing and virtualization. The document was prepared by Acácio Oliveira for Security+ study.
Security+ Lesson 01 Topic 05 - Common Network Protocols.pptxAcácio Oliveira
This document provides an overview of the topics to be covered in a 30-minute Common Network Protocols lesson for CompTIA Security+ certification preparation. The lesson will be divided into three parts covering IPv4 and IPv6, network storage protocols, the difference between ports and protocols, common protocols, and end-to-end security.
This document provides a 10 minute overview of incident response concepts for Security+ certification preparation. It discusses first responder responsibilities during security incidents and outlines incident response procedures and concepts covered in the Security+ study guide. The document is titled "Incident Response Concepts" and was prepared by Acácio Oliveira in 2021 as part of a Security+ study guide.
Security+ Lesson 01 Topic 12 - Security Related Awareness and Training.pptxAcácio Oliveira
This document discusses security related awareness and training. It covers the security policy, security awareness, and is part of a study guide for the CompTIA Security+ exam. The topic is allocated 10 minutes as part of the study guide index.
Security+ Lesson 01 Topic 17 - Types of Malware.pptxAcácio Oliveira
Malware is defined and common types are discussed including viruses, worms, Trojans, ransomware, and spyware. The document provides an overview of different types of malware for 10 minutes as part of a CompTIA Security+ study guide on the topic of types of malware.
Nunit vs XUnit vs MSTest Differences Between These Unit Testing Frameworks.pdfflufftailshop
When it comes to unit testing in the .NET ecosystem, developers have a wide range of options available. Among the most popular choices are NUnit, XUnit, and MSTest. These unit testing frameworks provide essential tools and features to help ensure the quality and reliability of code. However, understanding the differences between these frameworks is crucial for selecting the most suitable one for your projects.
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.
Salesforce Integration for Bonterra Impact Management (fka Social Solutions A...Jeffrey Haguewood
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Best 20 SEO Techniques To Improve Website Visibility In SERPPixlogix Infotech
Boost your website's visibility with proven SEO techniques! Our latest blog dives into essential strategies to enhance your online presence, increase traffic, and rank higher on search engines. From keyword optimization to quality content creation, learn how to make your site stand out in the crowded digital landscape. Discover actionable tips and expert insights to elevate your SEO game.
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Digital Marketing Trends in 2024 | Guide for Staying AheadWask
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Feeling lost in the digital marketing whirlwind of 2024? Technology is changing, consumer habits are evolving, and staying ahead of the curve feels like a never-ending pursuit. This e-book is your compass. Dive into actionable insights to handle the complexities of modern marketing. From hyper-personalization to the power of user-generated content, learn how to build long-term relationships with your audience and unlock the secrets to success in the ever-shifting digital landscape.
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How to Interpret Trends in the Kalyan Rajdhani Mix Chart.pdfChart Kalyan
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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
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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
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7. What is Prometheus?
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8. Monitoring Application Metrics with Prometheus
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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.
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.
8. CoreLinuxforRedHatandFedoralearningunderGNUFreeDocumentationLicense-Copyleft(c)AcácioOliveira2012
Everyoneispermittedtocopyanddistributeverbatimcopiesofthislicensedocument,changingisallowed
apps own LOGS
8
Troubleshooting tools
not all software uses the syslog framework to handle it’s logging.
Some software manages it’s own logs.
Can be difficult to track down all of the log locations on an unfamiliar system.
Best way to handle this is to start from the init scripts.
LOCATING APPLICATION LOGS:
1.To track log file local for an apps, find it’s configuration file and see where the logs are being written.
2.Finding the configuration file might be difficult, so it’s best to start at source.
3.init starts all of system services, so there is an init script that is starting up the apps in question.
4.The init script almost always references the configuration file
5.If the configuration file location is known, scan it and find out where the logs are being written.
6.The format of the log file its completely dependent on the application.
Some will be similar to syslog, others, like Apache or Qmail, will be completely foreign looking.
10. CoreLinuxforRedHatandFedoralearningunderGNUFreeDocumentationLicense-Copyleft(c)AcácioOliveira2012
Everyoneispermittedtocopyanddistributeverbatimcopiesofthislicensedocument,changingisallowed
tools
10
uptime Reports system uptime along with load averages.
•Load Average: Average number of processes in run queue that are blocked.
•uptime reports three values: the load averaged over the last 1 minute, 5 minutes and 15
minutes. This is useful to get an idea of the load trend on the system.
Troubleshooting tools
free reports on memory and swap usage
•buffers: I/O buffers, directory cache
•cached: filesystem cache (data)
[root@dev1 ~]# uptime
16:09:55 up 682 days, 10:11, 1 user, load average: 0.00, 0.01, 0.00
[root@dev1 ~]#
Ex:
[[root@dev1 ~]# free
total used free shared buffers cached
Mem: 262316 214228 48088 0 1168
41728
-/+ buffers/cache: 171332 90984
Swap: 524280 74564 449716
[root@dev1 ~]#
Ex:
11. CoreLinuxforRedHatandFedoralearningunderGNUFreeDocumentationLicense-Copyleft(c)AcácioOliveira2012
Everyoneispermittedtocopyanddistributeverbatimcopiesofthislicensedocument,changingisallowed
tools
11
Troubleshooting tools
w uptime report, with breakdown of logged-in users and process they are running
•JCPU: Combined CPU time of all processes attached to terminal (foreground and background)
•PCPU: CPU time of foreground process, listed in “what” column
vmstat Snapshot report covering several primary statistics.
•procs: number of running and blocked processes
•swap: swapped in and swapped out blocks of memory, per second
•io: blocks in and blocks out read/written per second
•system: interrupts and context switches per second
•cpu: user, system, idle, wait and time-stolen from a VM
[root@dev1 ~]# w
16:26:42 up 682 days, 10:28, 2 users, load average: 0.02, 0.05, 0.02
USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT
root pts/0 216-110-93-126.s 16:00 3:57 0.01s 0.01s -bash
root pts/9 216-110-93-126.s 16:22 0.00s 0.01s 0.00s w
Ex:
[root@dev1 ~]# vmstat
procs ----------memory---------- ---swap-- -----io---- --system-- -----cpu------
r b swpd free buff cache si so bi bo in cs us sy id wa st
0 0 74564 3608 4456 70156 0 0 0 2 0 0 0 0 100 0 0
Ex:
12. CoreLinuxforRedHatandFedoralearningunderGNUFreeDocumentationLicense-Copyleft(c)AcácioOliveira2012
Everyoneispermittedtocopyanddistributeverbatimcopiesofthislicensedocument,changingisallowed
tools
12
top Self-updating tool displays combination summary at top, followed by ordered
list of processes. Fully customizable.
• The summary includes uptime information, memory
• breakdowns, CPU utilization and process state summaries
Troubleshooting tools
top - 16:39:32 up 682 days, 10:41, 2 users, load average: 0.01, 0.00, 0.00
Tasks: 118 total, 1 running, 116 sleeping, 1 stopped, 0 zombie
Cpu(s): 0.1%us, 0.0%sy, 0.0%ni, 99.8%id, 0.0%wa, 0.0%hi, 0.0%si, 0.1%st
Mem: 262316k total, 258024k used, 4292k free, 7380k buffers
Swap: 524280k total, 74564k used, 449716k free, 67808k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
1 root 15 0 10316 648 592 S 0 0.2 0:06.24 init
2 root RT 0 0 0 0 S 0 0.0 0:04.88 migration/0
3 root 34 19 0 0 0 S 0 0.0 0:00.19 ksoftirqd/0
Ex:
13. CoreLinuxforRedHatandFedoralearningunderGNUFreeDocumentationLicense-Copyleft(c)AcácioOliveira2012
Everyoneispermittedtocopyanddistributeverbatimcopiesofthislicensedocument,changingisallowed
tools
13
Troubleshooting tools
df lists filesystem utilization
•Breaks down size and use information for each mounted filesystem
•-h is useful option to display in “human-friendly” format
[root@dev1 ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 9.4G 7.2G 1.8G 81% /
none 129M 0 129M 0% /dev/shm
Ex:
ldd List library dependencies
Ldconfig Update library location database
•/etc/ld.so.conf and /etc/ld.so.conf.d/*.conf for list of pathnames to search
for libraries, creates database for dynamic linker
[root@dev1 ~]# ldd /bin/bash
! libtermcap.so.2 => /lib64/libtermcap.so.2 (0x00002ac044572000)
! libdl.so.2 => /lib64/libdl.so.2 (0x00002ac044775000)
! libc.so.6 => /lib64/libc.so.6 (0x00002ac044979000)
! /lib64/ld-linux-x86-64.so.2 (0x00002ac044357000)
[root@dev1 ~]# cat /etc/ld.so.conf.d/mysql-x86_64.conf
/usr/lib64/mysql
[root@dev1 ~]# ldconfig
Ex: