57d0b251a6
- signed-off-by: trimstray <trimstray@gmail.com> |
||
---|---|---|
doc/img | ||
.gitignore | ||
CODE_OF_CONDUCT.md | ||
CONTRIBUTING.md | ||
LICENSE.md | ||
README.md |
A collection of awesome lists, manuals, blogs, hacks, one-liners, cli/web tools and more.
๐ What is it?
This list is a collection of various materials that I use every day in my work. It contain a lot of useful information gathered in one piece.
๐ป For whom?
It is intended for everyone and anyone - especially for System and Network Administrators, DevOps, Pentesters or Security Researchers.
โน๏ธ Contributing
A few simple rules for this project:
- inviting and clear
- not tiring
- useful
These below rules may be better:
- easy to contribute to (Markdown + HTML)
- easy to find (no TOC)
Url marked * is temporary unavailable. Please don't delete it without confirming that it has permanently expired.
Before add pull request please see this. All suggestions/PR are welcome!
โ๏ธ Todo
- Add useful shell functions
- Add one-liners for collection tools (eg. CLI Tools)
- Generate book pdf format
๐ข The Book of Secret Knowledge (Chapters)
CLI Tools
โช๏ธ Shells
๐ธ Oh My ZSH! - the best framework for managing your Zsh configuration.
๐ธ bash-it - framework for using, developing and maintaining shell scripts and custom commands for your daily work.
๐ธ Oh My Fish - the Fishshell framework.
โช๏ธ Managers
๐ธ Midnight Commander - visual file manager, licensed under GNU General Public License.
๐ธ screen - full-screen window manager that multiplexes a physical terminal.
๐ธ tmux - terminal multiplexer, lets you switch easily between several programs in one terminal.
๐ธ tmux-cssh - sets a comfortable and easy to use functionality, clustering and synchronizing virtual tmux-sessions.
โช๏ธ Network
๐ธ nmap - free and open source (license) utility for network discovery and security auditing.
๐ธ hping - command-line oriented TCP/IP packet assembler/analyzer.
๐ธ mtr - functionality of the 'traceroute' and 'ping' programs in a single network diagnostic tool.
๐ธ masscan - the fastest Internet port scanner, spews SYN packets asynchronously.
๐ธ netcat - networking utility which reads and writes data across network connections, using the TCP/IP protocol.
๐ธ tcpdump - powerful command-line packet analyzer.
๐ธ tshark - dump and analyze network traffic (wireshark cli).
๐ธ bmon - monitoring and debugging tool to capture networking related statistics and prepare them visually.
๐ธ Nemesis - packet manipulation CLI tool; craft and inject packets of several protocols.
๐ธ packetfu - a mid-level packet manipulation library for Ruby.
๐ธ Scapy - packet manipulation library; forge, send, decode, capture packets of a wide number of protocols.
๐ธ iptraf-ng - is a console-based network monitoring program for Linux that displays information about IP traffic.
๐ธ aria2 - is a lightweight multi-protocol & multi-source command-line download utility.
๐ธ Lynx - is a text browser for the World Wide Web.
โช๏ธ Network (DNS)
๐ธ fierce - a DNS reconnaissance tool for locating non-contiguous IP space.
๐ธ sublist3r - fast subdomains enumeration tool for penetration testers.
๐ธ amass - tool obtains subdomain names by scraping data sources, crawling web archives and more.
๐ธ namebench - provides personalized DNS server recommendations based on your browsing history.
โช๏ธ Network (HTTP)
๐ธ Curl - command line tool and library for transferring data with URLs.
๐ธ kurly - is an alternative to the widely popular curl program, written in Golang.
๐ธ HTTPie - a user-friendly HTTP client.
๐ธ wuzz - interactive cli tool for HTTP inspection.
๐ธ htrace.sh - shell script to debugging http/https; ssllabs, mozilla observatory, testssl.sh and nmap nse support.
๐ธ httpstat - visualizes curl statistics in a way of beauty and clarity.
๐ธ bombardier - fast cross-platform HTTP benchmarking tool written in Go.
๐ธ gobench - http/https load testing and benchmarking tool.
๐ธ gobuster - free and open source directory/file & DNS busting tool written in Go
โช๏ธ SSL/Security
๐ธ gnutls-cli - client program to set up a TLS connection to some other computer.
๐ธ sslyze
- fast and powerful SSL/TLS server scanning library.
๐ธ sslscan - tests SSL/TLS enabled services to discover supported cipher suites.
๐ธ testssl.sh - testing TLS/SSL encryption anywhere on any port.
๐ธ spiped - is a utility for creating symmetrically encrypted and authenticated pipes between socket addresses.
โช๏ธ Auditing Tools
๐ธ lynis - battle-tested security tool for systems running Linux, macOS, or Unix-based operating system.
๐ธ LinEnum - scripted Local Linux Enumeration & Privilege Escalation Checks.
๐ธ Rkhunter - scanner tool for Linux systems that scans backdoors, rootkits and local exploits on your systems.
โช๏ธ System Diagnostics/Debuggers
๐ธ strace - diagnostic, debugging and instructional userspace utility for Linux.
๐ธ DTrace - is a performance analysis and troubleshooting tool.
๐ธ ltrace - is a library call tracer, used to trace calls made by programs to library functions.
๐ธ sysdig - system exploration and troubleshooting tool with first class support for containers.
๐ธ glances - cross-platform system monitoring tool written in Python.
๐ธ htop - interactive text-mode process viewer for Unix systems. It aims to be a better 'top'.
๐ธ atop - ASCII performance monitor. Includes statistics for CPU, memory, disk, swap, network, and processes.
๐ธ lsof - displays in its output information about files that are opened by processes.
๐ธ FlameGraph - stack trace visualizer.
๐ธ lsofgraph - small utility to convert Unix lsof output to a graph showing FIFO and UNIX interprocess communication.
โช๏ธ Log Analyzers
๐ธ GoAccess - real-time web log analyzer and interactive viewer that runs in a terminal.
๐ธ ngxtop - real-time metrics for nginx server.
โช๏ธ Databases
๐ธ usql - universal command-line interface for SQL databases.
๐ธ pgcli - postgres CLI with autocompletion and syntax highlighting.
๐ธ mycli - terminal client for MySQL with autocompletion and syntax highlighting.
โช๏ธ TOR
๐ธ Nipe - script to make Tor Network your default gateway.
๐ธ multitor - a tool that lets you create multiple TOR instances with a load-balancing.
โช๏ธ Other
๐ธ incron - is an inode-based filesystem notification technology.
Web Tools
โช๏ธ SSL/Security
๐ธ SSL Server Test - free online service performs a deep analysis of the configuration of any SSL web server.
๐ธ SSL Server Test (DEV) - free online service performs a deep analysis of the configuration of any SSL web server.
๐ธ ImmuniWebยฎ SSLScan - test SSL/TLS (PCI DSS, HIPAA and NIST).
๐ธ urlscan.io - service to scan and analyse websites.
๐ธ Report URI - monitoring security policies like CSP and HPKP.
๐ธ CSP Evaluator - allows developers and security experts to check if a Content Security Policy.
๐ธ Useless CSP - public list about CSP in some big players (might make them care a bit more).
๐ธ Why No HTTPS? - list of the world's top 100 websites by Alexa rank not automatically redirecting insecure requests.
๐ธ cipherli.st - strong ciphers for Apache, Nginx, Lighttpd and more.
๐ธ badssl.com - memorable site for testing clients against bad SSL configs.
๐ธ tlsfun.de - registered for various tests regarding the TLS/SSL protocol.
๐ธ Common CA Database - repository of information about CAs, and their root and intermediate certificates.
๐ธ CERTSTREAM - real-time certificate transparency log update stream.
๐ธ crt.sh - discovers certificates by continually monitoring all of the publicly known CT.
โช๏ธ Privacy
๐ธ privacytools.io - provides knowledge and tools to protect your privacy against global mass surveillance.
๐ธ DNS Privacy Test Servers - DNS privacy recursive servers list (with a 'no logging' policy).
โช๏ธ HTTP Headers
๐ธ Security Headers - analyse the HTTP response headers (with rating system to the results).
๐ธ Observatory by Mozilla - set of tools to analyze your website.
๐ธ Enable CORS - enable cross-origin resource sharing.
โช๏ธ DNS
๐ธ ViewDNS - one source for free DNS related tools and information.
๐ธ DNSlytics - online investigation tool.
๐ธ DNS Spy - monitor, validate and verify your DNS configurations.
๐ธ Find subdomains online - find subdomains for security assessment penetration test.
๐ธ DNSdumpster - dns recon & research, find & lookup dns records.
๐ธ DNS Table online - search for DNS records by domain, IP, CIDR, ISP.
๐ธ PTRarchive.com - this site is responsible for the safekeeping of historical reverse DNS records.
๐ธ xip.ip - wildcard DNS for everyone.
โช๏ธ Mail
๐ธ MX Toolbox - all of your MX record, DNS, blacklist and SMTP diagnostics in one integrated tool.
๐ธ blacklistalert - checks to see if your domain is on a Real Time Spam Blacklist.
๐ธ MultiRBL - complete IP check for sending Mailservers.
โช๏ธ PGP Keyservers
๐ธ SKS OpenPGP Key server - includes a highly-efficient reconciliation algorithm for keeping the keyservers synchronized.
โช๏ธ Mass scanners (search engines)
๐ธ Censys - platform that helps information security practitioners discover, monitor, and analyze devices.
๐ธ Shodan - the world's first search engine for Internet-connected devices.
๐ธ Shodan 2000 - if you use Shodan for everyday work, be sure to see it - looks for randomly generated data from Shodan.
๐ธ GreyNoise - mass scanner (such as Shodan and Censys).
๐ธ ZoomEye - search engine for cyberspace that lets the user find specific network components.
๐ธ FOFA - is a cyberspace search engine.
๐ธ onyphe - is a search engine for open-source and cyber threat intelligence data collected.
๐ธ binaryedge - it scan the entire internet space and create real-time threat intelligence streams and reports.
๐ธ hunter - lets you find email addresses in seconds and connect with the people that matter for your business.
๐ธ wigle - is a submission-based catalog of wireless networks. All the networks. Found by Everyone.
๐ธ PublicWWW - find any alphanumeric snippet, signature or keyword in the web pages HTML, JS and CSS code.
๐ธ IntelTechniques - this repository contains hundreds of online search utilities.
๐ธ GhostProject? - search by full email address or username.
๐ธ Buckets by Grayhatwarfar - database with public search for Open Amazon S3 Buckets and their contents.
๐ธ Vigilante.pw - the breached database directory.
๐ธ builtwith - find out what websites are built with.
โช๏ธ Net-tools
๐ธ Netcraft - detailed report about the site, helping you to make informed choices about their integrity.
๐ธ RIPE NCC - not-for-profit membership association, a Regional Internet Registry and the secretariat for the RIPE.
๐ธ Robtex - uses various sources to gather public information about IP numbers, domain names, host names, routes etc.
๐ธ Security Trails - APIs for Security Companies, Researchers and Teams.
๐ธ Online Curl - curl test, analyze HTTP Response Headers.
๐ธ Ping.eu - online Ping, Traceroute, DNS lookup, WHOIS and others.
๐ธ Network-Tools - network tools for webmasters, IT technicians & geeks.
๐ธ URL Encode/Decode - tool from above to either encode or decode a string of text.
๐ธ Uncoder - the online translator for search queries on log data.
๐ธ XSS String Encoder - for generating XSS code to check your input validation filters against XSS.
๐ธ RegExr - online tool to learn, build, & test Regular Expressions (RegEx / RegExp).
๐ธ Hardenize - deploy the security standards.
๐ธ VirusTotal - analyze suspicious files and URLs to detect types of malware.
โช๏ธ Code parsers/playgrounds
๐ธ ShellCheck - finds bugs in your shell scripts.
๐ธ explainshell - get interactive help texts for shell commands.
๐ธ jsbin - live pastebin for HTML, CSS & JavaScript and more.
๐ธ PHP Sandbox - test your PHP code with this code tester.
๐ธ Repl.it - an instant IDE to learn, build, collaborate, and host all in one place.
โช๏ธ Performance
๐ธ GTmetrix - analyze your siteโs speed and make it faster.
๐ธ Sucuri loadtimetester - test here the
performance of any of your sites from across the globe.
๐ธ Pingdom Tools - analyze your siteโs speed around the world.
โช๏ธ Passwords
๐ธ Gotcha? - list of 1.4 billion accounts circulates around the Internet.
๐ธ have i been pwned? - check if you have an account that has been compromised in a data breach.
โช๏ธ CVE
๐ธ CVE Mitre - list of publicly known cybersecurity vulnerabilities.
๐ธ CVE Details - CVE security vulnerability advanced database.
๐ธ Exploit DB - CVE compliant archive of public exploits and corresponding vulnerable software.
Manuals/Howtos/Tutorials
โช๏ธ Bash
๐ธ pure-bash-bible - a collection of pure bash alternatives to external processes.
๐ธ The Bash Hackers Wiki - hold documentation of any kind about GNU Bash.
๐ธ Shell & Utilities - describes the commands and utilities offered to application programs by POSIX-conformant systems.
โช๏ธ Programming
๐ธ FโAwk Yeah! - advanced sed and awk usage (Parsing for Pentesters 3).
โช๏ธ Unix & Network
๐ธ nixCraft - linux and unix tutorials for new and seasoned sysadmin.
๐ธ TecMint - the ideal Linux blog for Sysadmins & Geeks.
๐ธ Omnisecu - Free Networking, System Administration and Security Tutorials.
๐ธ Unix Toolbox - collection of Unix/Linux/BSD commands and tasks which are useful for IT work or for advanced users.
โช๏ธ Security
๐ธ OWASP - worldwide not-for-profit charitable organization focused on improving the security of software.
๐ธ OWASP ASVS 3.0.1 - OWASP Application Security Verification Standard Project.
๐ธ OWASP ASVS 3.0.1 Web App - simple web app that helps developers understand the ASVS requirements.
๐ธ Offensive Security - true performance-based penetration testing training for over a decade.
๐ธ Hacking Articles - LRaj Chandel's Security & Hacking Blog.
๐ธ GTFOBins - list of Unix binaries that can be exploited by an attacker to bypass local security restrictions.
๐ธ AWS security tools - make your AWS cloud environment more secure.
๐ธ HTML5 Security Cheatsheet - a collection of HTML5 related XSS attack vectors.
๐ธ PTES - the penetration testing execution standard.
๐ธ ctf-tools - some setup scripts for security research tools.
๐ธ Guifre Ruiz Notes - collection of security, system, network and pentest cheatsheets.
๐ธ Rawsec's CyberSecurity Inventory - an inventory of tools and resources about CyberSecurity.
๐ธ Application Security Wiki - is an initiative to provide all application security related resources at one place.
๐ธ The Illustrated TLS Connection - every byte of a TLS connection explained and reproduced.
โช๏ธ Web Apps
๐ธ Mozilla Web Security - help operational teams with creating secure web applications.
โช๏ธ Other
๐ธ CTF Series : Vulnerable Machines - the steps below could be followed to find vulnerabilities and exploits.
๐ธ How to start RE/malware analysis? - collection of some hints and useful links for the beginners.
๐ธ LZone Cheat Sheets - all cheat sheets.
๐ธ Danโs Cheat Sheetsโs - massive cheat sheets documentation.
๐ธ The C10K problem - it's time for web servers to handle ten thousand clients simultaneously, don't you think?
๐ธ Bank Grade Security - when companies say they have "Bank Grade Security" they imply that it is a good thing.*
๐ธ HTTPS on Stack Overflow - this is the story of a long journey regarding the implementation of SSL.
๐ธ Julia's Drawings - some drawings about programming and unix world, zines about systems & debugging tools.
๐ธ DEF CON Media Server - great stuff from DEFCON 26.
๐ธ BGP Meets Cat - after 3072 hours of manipulating BGP, Job Snijders has succeeded in drawing a Nyancat.
๐ธ HTTPS in the real world - great tutorial explain how HTTPS works in the real world.
๐ธ Hidden directories - hidden directories and files as a source of sensitive information about web application.
Blogs
โช๏ธ Geeky Blogs
๐ธ Brendan Gregg's Blog - Brendan Gregg is an industry expert in computing performance and cloud computing.
๐ธ Gynvael "GynDream" Coldwind - Gynvael is a IT security engineer at Google.
๐ธ Michaล "lcamtuf" Zalewski - "white hat" hacker, computer security expert.
๐ธ Mattias Geniar - developer, Sysadmin, Blogger, Podcaster and Public Speaker.
๐ธ Nick Craver - Software Developer and Systems Administrator for Stack Exchange.
๐ธ Robert Penz - IT security Expert.
๐ธ Scott Helme - Security Researcher, international speaker and founder of securityheaders.com and report-uri.com.
๐ธ Kacper Szurek - Detection Engineer at ESET.
๐ธ Troy Hunt - Microsoft Regional Director and Microsoft Most Valuable Professional for Developer Security.
๐ธ Linux Audit - the Linux security blog about Auditing, Hardening and Compliance by Michael Boelen.
๐ธ
Linux Security Expert - trainings, howtos, checklists, security tools and more.
๐ธ The Grymoire - collection of useful incantations for wizards, be you computer wizards, magicians, or whatever.
๐ธ raymii.org - linux/unix sysadmin specializing in building high availability cloud environments.
โช๏ธ A piece of history
๐ธ How to Do Things at ARL - how to configure modems, scan images, record CD-ROMs, and other useful techniques.
Systems/Services
โช๏ธ Systems
๐ธ Slackware - the most "Unix-like" Linux distribution.
๐ธ OpenBSD - multi-platform 4.4BSD-based UNIX-like operating system.
๐ธ HardenedBSD - HardenedBSD aims to implement innovative exploit mitigation and security solutions.
๐ธ Kali Linux - Linux distribution used for Penetration Testing, Ethical Hacking and network security assessments.
๐ธ Backbox Linux - penetration test and security assessment oriented Ubuntu-based Linux distribution.
โช๏ธ HTTP(s) Services
๐ธ Varnish HTTP Cache - HTTP accelerator designed for content-heavy dynamic web sites.
๐ธ Nginx - open source web and reverse proxy server that is similar to Apache, but very light weight.
โช๏ธ Security/hardening
๐ธ Emerald Onion - seattle-based encrypted-transit internet service provider.
๐ธ Unbound - validating, recursive, and caching DNS resolver (with TLS).
๐ธ Knot Resolver - caching full resolver implementation, including both a resolver library and a daemon.
๐ธ Vulnreport - open-source pentesting management and automation platform by Salesforce Product Security.
Networks
โช๏ธ Tools
๐ธ CapAnalysis - web visual tool to analyze large amounts of captured network traffic (PCAP analyzer).
โช๏ธ Labs
๐ธ NRE Labs - learn automation by doing it. Right now, right here, in your browser.
Awesome Lists
๐ธ Awesome Sysadmin - amazingly awesome open source sysadmin resources.
๐ธ Awesome Shell - awesome command-line frameworks, toolkits, guides and gizmos.
๐ธ Awesome Hacking - awesome lists for hackers, pentesters and security researchers.
๐ธ Awesome Hacking Resources - collection of hacking/penetration testing resources to make you better.
๐ธ Hacking Cheat Sheet - author hacking and pentesting notes.
๐ธ Movies for Hackers - list of movies every hacker & cyberpunk must watch.
๐ธ Awesome Pentest - collection of awesome penetration testing resources, tools and other shiny things.
๐ธ Awesome Pcaptools - collection of tools developed by other researchers to process network traces.
๐ธ SecLists - collection of multiple types of lists used during security assessments, collected in one place.
๐ธ Command-line-text-processing - from finding text to search and replace, from sorting to beautifying text and more.
๐ธ Awesome Scalability - best practices in building High Scalability, High Availability, High Stability and more.
๐ธ Awesome Postgres - list of awesome PostgreSQL software, libraries, tools and resources.
๐ธ Free Security eBooks - list of a Free Security and Hacking eBooks.
Hacking/Penetration Testing
โช๏ธ Pentesters arsenal tools
๐ธ Metasploit - tool and framework for pentesting system, web and many more, contains a lot a ready to use exploit.
๐ธ Burp Suite - tool for testing Web application security, intercepting proxy to replay, inject, scan and fuzz HTTP requests.
๐ธ OWASP Zed Attack Proxy - intercepting proxy to replay, inject, scan and fuzz HTTP requests.
๐ธ Nikto2 - web server scanner which performs comprehensive tests against web servers for multiple items.
๐ธ sqlmap - tool that automates the process of detecting and exploiting SQL injection flaws.
โช๏ธ Pentests bookmarks collection
๐ธ Brute XSS - master the art of Cross Site Scripting.
๐ธ Offensive Security Bookmarks - security bookmarks collection, all that things I need to pass OSCP.
๐ธ Awesome Pentest Cheat Sheets - collection of the cheat sheets useful for pentesting.
๐ธ Pentest Bookmarks - there are a LOT of pentesting blogs.
๐ธ PayloadsAllTheThings - a list of useful payloads and bypass for Web Application Security and Pentest/CTF.
๐ธ Pentesting Tools Cheat Sheet - a quick reference high level overview for typical penetration testing engagements.
๐ธ SQL Injection Cheat Sheet - detailed technical information about the many different variants of the SQL Injection.
๐ธ Entersoft Knowledge Base - great and detailed reference about vulnerabilities.
โช๏ธ Bounty programs
๐ธ Bounty Factory - European bug bounty platform based on the legislation and rules in force in European countries.
๐ธ Openbugbounty - allows any security researcher reporting a vulnerability on any website.
๐ธ hackerone - global hacker community to surface the most relevant security issues.
๐ธ bugcrowd - crowdsourced cybersecurity for the enterprise.
๐ธ Crowdshield - crowdsourced Security & Bug Bounty Management.
โช๏ธ Web Training Apps (local installation)
๐ธ OWASP-VWAD - comprehensive and well maintained registry of all known vulnerable web applications.
๐ธ Metasploitable 2 - vulnerable web application amongst security researchers.
๐ธ DVWA - PHP/MySQL web application that is damn vulnerable.
๐ธ OWASP Mutillidae II - free, open source, deliberately vulnerable web-application.
๐ธ OWASP Juice Shop Project - the most bug-free vulnerable application in existence.
๐ธ OWASP WebGoat Project - insecure web application maintained by OWASP designed to teach web app security.
๐ธ Security Ninjas - open source application security training program.
๐ธ hackazon - a modern vulnerable web app.
๐ธ dvna - damn vulnerable NodeJS application.
๐ธ Google Gruyere - web application exploits and defenses.
๐ธ Bodhi - is a playground focused on learning the exploitation of client-side web vulnerabilities.
โช๏ธ Labs (ethical hacking platforms)
๐ธ Hack The Box - online platform allowing you to test your penetration testing skills.
๐ธ Hacking-Lab - online ethical hacking, computer network and security challenge platform.
๐ธ pwnable.kr - non-commercial wargame site which provides various pwn challenges regarding system exploitation.
๐ธ Pwnable.tw - is a wargame site for hackers to test and expand their binary exploiting skills.
๐ธ Silesia Security Lab - high quality security testing services.
๐ธ Practical Pentest Labs - pentest lab, take your Hacking skills to the next level.
๐ธ Root Me - the fast, easy, and affordable way to train your hacking skills.
๐ธ rozwal.to - a great platform to train your pentesting skills.
๐ธ TryHackMe - learning Cyber Security made easy.
๐ธ OverTheWire - can help you to learn and practice security concepts in the form of fun-filled games.
๐ธ Wizard Labs - is an online Penetration Testing Lab.
๐ธ PentesterLab - provides vulnerable systems that can be used to test and understand vulnerabilities.
๐ธ RingZer0 - tons of challenges designed to test and improve your hacking skills.
๐ธ Ubeeri - preconfigured lab environments.
๐ธ Pentestit - emulate an IT infrastructure of real companies for a legal pen testing and improving penetration testing skills.
Your daily knowledge and news
โช๏ธ RSS Readers
๐ธ Feedly - organize, read and share what matters to you.
โช๏ธ Security
๐ธ Google Online Security Blog - the latest news and insights from Google on security and safety on the Internet.
๐ธ Qualys Blog - expert network security guidance and news.
๐ธ DARKReading - connecting the Information Security Community.
๐ธ publiclyDisclosed - public disclosure watcher who keeps you up to date about the recently disclosed bugs.
๐ธ 0day.today - exploits market provides you the possibility to buy zero-day exploits and also to sell 0day exploits.
๐ธ sploitus - the exploit and tools database.
๐ธ Packet Storm - information security services, news, files, tools, exploits, aAdvisories and whitepapers.
๐ธ Sekurak - about security, penetration tests, vulnerabilities and many others (PL/EN).
๐ธ nf.sec - basic aspects and mechanisms of Linux operating system security (PL).
Other Cheat Sheets
DNS Servers list (privacy)
IP | URL |
---|---|
84.200.69.80 |
dns.watch |
94.247.43.254 |
opennic.org |
64.6.64.6 |
verisign.com |
89.233.43.71 |
censurfridns.dk |
1.1.1.1 |
cloudflare.com |
94.130.110.185 |
dnsprivacy.at |
Build your own DNS Servers
๐ธ Unbound DNS Tutorial - a validating, recursive, and caching DNS server.
๐ธ Knot Resolver on Fedora - how to get faster and more secure DNS resolution with Knot Resolver on Fedora.
๐ธ DNS-over-HTTPS - tutorial to setup your own DNS-over-HTTPS (DoH) server.
๐ธ DNS Servers - how (and why) i run my own DNS Servers.
๐ธ DNS Privacy Server - running your own DoT or DoH server this page provides some ideas.
One-liners
Table of Contents
Tool: terminal
Reload shell without exit
exec $SHELL -l
Close shell keeping all subprocess running
disown -a && exit
Exit without saving shell history
kill -9 $$
unset HISTFILE && exit
Perform a branching conditional
true && echo success
false || echo failed
Pipe stdout and stderr to separate commands
some_command > >(/bin/cmd_for_stdout) 2> >(/bin/cmd_for_stderr)
Redirect stdout and stderr each to separate files and print both to the screen
(some_command 2>&1 1>&3 | tee errorlog ) 3>&1 1>&2 | tee stdoutlog
List of commands you use most often
history | \
awk '{CMD[$2]++;count++;}END { for (a in CMD)print CMD[a] " " CMD[a]/count*100 "% " a;}' | \
grep -v "./" | \
column -c3 -s " " -t | \
sort -nr | nl | head -n 20
Quickly backup a file
cp filename{,.orig}
Empty a file (truncate to 0 size)
>filename
Delete all files in a folder that don't match a certain file extension
rm !(*.foo|*.bar|*.baz)
Pass multi-line string to a file
# cat >filename ... - overwrite file
# cat >>filename ... - append to file
cat > filename << __EOF__
data data data
__EOF__
Edit a file on a remote host using vim
vim scp://user@host//etc/fstab
Create a directory and change into it at the same time
mkd () { mkdir -p "$@" && cd "$@"; }
Convert uppercase files to lowercase files
rename 'y/A-Z/a-z/' *
Print a row of characters across the terminal
printf "%`tput cols`s" | tr ' ' '#'
Show shell history without line numbers
history | cut -c 8-
fc -l -n 1 | sed 's/^\s*//'
Run command(s) after exit session
cat > /etc/profile << __EOF__
_after_logout() {
username=$(whoami)
for _pid in $(ps afx | grep sshd | grep "$username" | awk '{print $1}') ; do
kill -9 $_pid
done
}
trap _after_logout EXIT
__EOF__
Generate a sequence of numbers
for ((i=1; i<=10; i+=2)) ; do echo $i ; done
# alternative: seq 1 2 10
for ((i=5; i<=10; ++i)) ; do printf '%02d\n' $i ; done
# alternative: seq -w 5 10
Tool: mount
Mount a temporary ram partition
mount -t tmpfs tmpfs /mnt -o size=64M
-t
- filesystem type-o
- mount options
Remount a filesystem as read/write
mount -o remount,rw /
Tool: fuser
Kills a process that is locking a file
fuser -k filename
Show what PID is listening on specific port
fuser -v 53/udp
Tool: ps
Show a 4-way scrollable process tree with full details
ps awwfux | less -S
Processes per user counter
ps hax -o user | sort | uniq -c | sort -r
Tool: find
Find files that have been modified on your system in the past 60 minutes
find / -mmin 60 -type f
Find all files larger than 20M
find / -type f -size +20M
Find duplicate files (based on MD5 hash)
find -type f -exec md5sum '{}' ';' | sort | uniq --all-repeated=separate -w 33
Change permission only for files
cd /var/www/site && find . -type f -exec chmod 766 {} \;
cd /var/www/site && find . -type f -exec chmod 664 {} +
Change permission only for directories
cd /var/www/site && find . -type d -exec chmod g+x {} \;
cd /var/www/site && find . -type d -exec chmod g+rwx {} +
Find files and directories for specific user
find . -user <username> -print
Find files and directories for all without specific user
find . \!-user <username> -print
Delete older files than 60 days
find . -type f -mtime +60 -delete
Recursively remove all empty sub-directories from a directory
find . -depth -type d -empty -exec rmdir {} \;
How to find all hard links to a file
find </path/to/dir> -xdev -samefile filename
Recursively find the latest modified files
find . -type f -exec stat --format '%Y :%y %n' "{}" \; | sort -nr | cut -d: -f2- | head
Tool: top
Use top to monitor only all processes with the specific string
top -p $(pgrep -d , <str>)
<str>
- process containing str (eg. nginx, worker)
Tool: strace
Track child process
strace -f -p $(pidof glusterfsd)
Track process after 30 seconds
timeout 30 strace $(< /var/run/zabbix/zabbix_agentd.pid)
Track child process and redirect output to a file
ps auxw | grep 'sbin/[a]pache' | awk '{print " -p " $2}' | xargs strace -o /tmp/strace-apache-proc.out
Track the open request of a network port
strace -f -e trace=bind nc -l 80
Track the open request of a network port (show TCP/UDP)
strace -f -e trace=network nc -lu 80
Tool: kill
Kill a process running on port
kill -9 $(lsof -i :<port> | awk '{l=$2} END {print l}')
Tool: diff
Compare two directory trees
diff <(cd directory1 && find | sort) <(cd directory2 && find | sort)
Tool: tail
Annotate tail -f with timestamps
tail -f file | while read ; do echo "$(date +%T.%N) $REPLY" ; done
Analyse an Apache access log for the most common IP addresses
tail -10000 access_log | awk '{print $1}' | sort | uniq -c | sort -n | tail
Analyse web server log and show only 5xx http codes
tail -n 100 -f /path/to/logfile | grep "HTTP/[1-2].[0-1]\" [5]"
Tool: tar
System backup with exclude specific directories
cd /
tar -czvpf /mnt/system$(date +%d%m%Y%s).tgz --directory=/ \
--exclude=proc/* --exclude=sys/* --exclude=dev/* --exclude=mnt/* .
System backup with exclude specific directories (pigz)
cd /
tar cvpf /backup/snapshot-$(date +%d%m%Y%s).tgz --directory=/ \
--exclude=proc/* --exclude=sys/* --exclude=dev/* \
--exclude=mnt/* --exclude=tmp/* --use-compress-program=pigz .
Tool: dump
System backup to file
dump -y -u -f /backup/system$(date +%d%m%Y%s).lzo /
Restore system from lzo file
cd /
restore -rf /backup/system$(date +%d%m%Y%s).lzo
Tool: cpulimit
Limit the cpu usage of a process
cpulimit -p pid -l 50
Tool: pwdx
Show current working directory of a process
pwdx <pid>
Tool: taskset
Start a command on only one CPU core
taskset -c 0 <command>
Tool: tr
Show directories in the PATH, one per line
tr : '\n' <<<$PATH
Tool: chmod
Remove executable bit from all files in the current directory
chmod -R -x+X *
Restore permission for /bin/chmod
# 1:
cp /bin/ls chmod.01
cp /bin/chmod chmod.01
./chmod.01 700 file
# 2:
/bin/busybox chmod 0700 /bin/chmod
# 3:
setfacl --set u::rwx,g::---,o::--- /bin/chmod
Tool: who
Find last reboot time
who -b
Tool: screen
Start screen in detached mode
screen -d -m [<command>]
Tool: du
Show 20 biggest directories with 'K M G'
du | \
sort -r -n | \
awk '{split("K M G",v); s=1; while($1>1024){$1/=1024; s++} print int($1)" "v[s]"\t"$2}' | \
head -n 20
Tool: inotifywait
Init tool everytime a file in a directory is modified
while true ; do inotifywait -r -e MODIFY dir/ && ls dir/ ; done;
Tool: openssl
Testing connection to remote host
echo | openssl s_client -connect google.com:443 -showcerts
Testing connection to remote host (with SNI support)
echo | openssl s_client -showcerts -servername google.com -connect google.com:443
Testing connection to remote host with specific ssl version
openssl s_client -tls1_2 -connect google.com:443
Testing connection to remote host with specific ssl cipher
openssl s_client -cipher 'AES128-SHA' -connect google.com:443
Generate private key
# _ciph: des3, aes
( _ciph="des3" ; _fd="private.key" ; _len="2048" ; \
openssl genrsa -${_ciph} -out ${_fd} ${_len} )
Remove password from private key
( _fd="private.key" ; _fd_unp="private_unp.key" ; \
openssl rsa -in ${_fd} -out ${_fd_unp} )
Get public key from private key
( _fd="private.key" ; _fd_pub="public.key" ; \
openssl rsa -pubout -in ${_fd} -out ${_fd_pub} )
Generate private key + csr
( _fd="private.key" ; _fd_csr="request.csr" ; _len="2048" ; \
openssl req -out ${_fd_csr} -new -newkey rsa:${_len} -nodes -keyout ${_fd} )
Generate csr
( _fd="private.key" ; _fd_csr="request.csr" ; \
openssl req -out ${_fd_csr} -new -key ${_fd} )
Generate csr (metadata from exist certificate)
( _fd="private.key" ; _fd_csr="request.csr" ; _fd_crt="cert.crt" ; \
openssl x509 -x509toreq -in ${_fd_crt} -out ${_fd_csr} -signkey ${_fd} )
Generate csr with -config param
( _fd="private.key" ; _fd_csr="request.csr" ; \
openssl req -new -sha256 -key ${_fd} -out ${_fd_csr} \
-config <(
cat <<-EOF
[req]
default_bits = 2048
prompt = no
default_md = sha256
req_extensions = req_ext
distinguished_name = dn
[ dn ]
C=<two-letter ISO abbreviation for your country>
ST=<state or province where your organization is legally located>
L=<city where your organization is legally located>
O=<legal name of your organization>
OU=<section of the organization>
CN=<fully qualified domain name>
[ req_ext ]
subjectAltName = @alt_names
[ alt_names ]
DNS.1 = <fully qualified domain name>
DNS.2 = <next domain>
DNS.3 = <next domain>
EOF
))
Convert DER to PEM
( _fd_der="cert.crt" ; _fd_pem="cert.pem" ; \
openssl x509 -in ${_fd_der} -inform der -outform pem -out ${_fd_pem} )
Convert PEM to DER
( _fd_der="cert.crt" ; _fd_pem="cert.pem" ; \
openssl x509 -in ${_fd_pem} -outform der -out ${_fd_der} )
Checking whether the private key and the certificate match
(openssl rsa -noout -modulus -in private.key | openssl md5 ; openssl x509 -noout -modulus -in certificate.crt | openssl md5) | uniq
Tool: gnutls-cli
Testing connection to remote host (with SNI support)
gnutls-cli -p 443 google.com
Testing connection to remote host (without SNI support)
gnutls-cli --disable-sni -p 443 google.com
Tool: secure-delete
Secure delete with shred
shred -vfuz -n 10 file
shred --verbose --random-source=/dev/urandom -n 1 /dev/sda
Secure delete with scrub
scrub -p dod /dev/sda
scrub -p dod -r file
Secure delete with badblocks
badblocks -s -w -t random -v /dev/sda
badblocks -c 10240 -s -w -t random -v /dev/sda
Secure delete with secure-delete
srm -vz /tmp/file
sfill -vz /local
sdmem -v
swapoff /dev/sda5 && sswap -vz /dev/sda5
Tool: dd
Show dd status every so often
dd <dd_params> status=progress
watch --interval 5 killall -USR1 dd
Redirect output to a file with dd
echo "string" | dd of=filename
Tool: curl
curl -Iks https://www.google.com
-I
- show response headers only-k
- insecure connection when using ssl-s
- silent mode (not display body)
curl -Iks --location -X GET -A "x-agent" https://www.google.com
--location
- follow redirects-X
- set method-A
- set user-agent
curl -Iks --location -X GET -A "x-agent" --proxy http://127.0.0.1:16379 https://www.google.com
--proxy [socks5://|http://]
- set proxy server
Check DNS and HTTP trace with headers for specific domains
### Set domains and external dns servers.
_domain_list=(google.com) ; _dns_list=("8.8.8.8" "1.1.1.1")
for _domain in "${_domain_list[@]}" ; do
printf '=%.0s' {1..48}
echo
printf "[\\e[1;32m+\\e[m] resolve: %s\\n" "$_domain"
for _dns in "${_dns_list[@]}" ; do
# Resolve domain.
host "${_domain}" "${_dns}"
echo
done
for _proto in http https ; do
printf "[\\e[1;32m+\\e[m] trace + headers: %s://%s\\n" "$_proto" "$_domain"
# Get trace and http headers.
curl -Iks -A "x-agent" --location "${_proto}://${_domain}"
echo
done
done
unset _domain_list _dns_list
Tool: httpie
http -p Hh https://www.google.com
-p
- print request and response headersH
- request headersB
- request bodyh
- response headersb
- response body
http -p Hh --follow --max-redirects 5 --verify no https://www.google.com
-F, --follow
- follow redirects--max-redirects N
- maximum for--follow
--verify no
- skip SSL verification
http -p Hh --follow --max-redirects 5 --verify no --proxy http:http://127.0.0.1:16379 https://www.google.com
--proxy [http:]
- set proxy server
Tool: ssh
Compare a remote file with a local file
ssh user@host cat /path/to/remotefile | diff /path/to/localfile -
SSH connection through host in the middle
ssh -t reachable_host ssh unreachable_host
Run command over ssh on remote host
cat > cmd.txt << __EOF__
cat /etc/hosts
__EOF__
ssh host -l user $(<cmd.txt)
Get public key from private key
ssh-keygen -y -f ~/.ssh/id_rsa
Get all fingerprints
ssh-keygen -l -f .ssh/known_hosts
Ssh authentication with user password
ssh -o PreferredAuthentications=password -o PubkeyAuthentication=no user@remote_host
Ssh authentication with publickey
ssh -o PreferredAuthentications=publickey -o PubkeyAuthentication=yes -i id_rsa user@remote_host
Simple recording SSH session
function _ssh_sesslog() {
_sesdir="<path/to/session/logs>"
mkdir -p "${_sesdir}" && \
ssh $@ 2>&1 | tee -a "${_sesdir}/$(date +%Y%m%d).log"
}
# Alias:
alias ssh='_ssh_sesslog'
Using Keychain for SSH logins
### Delete all of ssh-agent's keys.
function _scl() {
/usr/bin/keychain --clear
}
### Add key to keychain.
function _scg() {
/usr/bin/keychain /path/to/private-key
source "$HOME/.keychain/$HOSTNAME-sh"
}
Tool: linux-dev
Testing remote connection to port
timeout 1 bash -c "</dev/<proto>/<host>/<port>" >/dev/null 2>&1 ; echo $?
<proto
- set protocol (tcp/udp)<host>
- set remote host<port>
- set destination port
Read and write to TCP or UDP sockets with common bash tools
exec 5<>/dev/tcp/<host>/<port>; cat <&5 & cat >&5; exec 5>&-
Tool: tcpdump
tcpdump -ne -i eth0 -Q in host 192.168.252.1 and port 443
-n
- don't convert addresses-e
- print the link-level headers-i [iface|any]
- set interface-Q|-D [in|out|inout]
- choose send/receive direction (-D
- for old tcpdump versions)host [ip|hostname]
- set host, also[host not]
[and|or]
- set logicport [1-65535]
- set port number, also[port not]
tcpdump -ne -i eth0 -Q in host 192.168.252.1 and port 443 -c 5 -w tcpdump.pcap
-c [num]
- capture only num number of packets-w [filename]
- write packets to file,-r [filename]
- reading from file
Tool: tcpick
Analyse packets in real-time
while true ; do tcpick -a -C -r dump.pcap ; sleep 2 ; clear ; done
Tool: ngrep
ngrep -d eth0 "www.google.com" port 443
-d [iface|any]
- set interface[domain]
- set hostnameport [1-65535]
- set port number
ngrep -d eth0 "www.google.com" (host 10.240.20.2) and (port 443)
(host [ip|hostname])
- filter by ip or hostname(port [1-65535])
- filter by port number
ngrep -d eth0 -qt -O ngrep.pcap "www.google.com" port 443
-q
- quiet mode (only payloads)-t
- added timestamps-O [filename]
- save output to file,-I [filename]
- reading from file
ngrep -d eth0 -qt 'HTTP' 'tcp'
HTTP
- show http headerstcp|udp
- set protocol[src|dst] host [ip|hostname]
- set direction for specific node
ngrep -l -q -d eth0 -i "User-Agent: curl*"
-l
- stdout line buffered-i
- case-insensitive search
Tool: hping3
hping3 -V -p 80 -s 5050 <scan_type> www.google.com
-V|--verbose
- verbose mode-p|--destport
- set destination port-s|--baseport
- set source port<scan_type>
- set scan type-F|--fin
- set FIN flag, port open if no reply-S|--syn
- set SYN flag-P|--push
- set PUSH flag-A|--ack
- set ACK flag (use when ping is blocked, RST response back if the port is open)-U|--urg
- set URG flag-Y|--ymas
- set Y unused flag (0x80 - nullscan), port open if no reply-M 0 -UPF
- set TCP sequence number and scan type (URG+PUSH+FIN), port open if no reply
hping3 -V -c 1 -1 -C 8 www.google.com
-c [num]
- packet count-1
- set ICMP mode-C|--icmptype [icmp-num]
- set icmp type (default icmp-echo = 8)
hping3 -V -c 1000000 -d 120 -S -w 64 -p 80 --flood --rand-source <remote_host>
--flood
- sent packets as fast as possible (don't show replies)--rand-source
- random source address mode-d --data
- data size-w|--win
- winsize (default 64)
Tool: netcat
nc -kl 5000
-l
- listen for an incoming connection-k
- listening after client has disconnected>filename.out
- save receive data to file (optional)
nc 192.168.0.1 5051 < filename.in
< filename.in
- send data to remote host
nc -vz 10.240.30.3 5000
-v
- verbose output-z
- scan for listening daemons
nc -vzu 10.240.30.3 1-65535
-u
- scan only udp ports
Transfer data file (archive)
server> nc -l 5000 | tar xzvfp -
client> tar czvfp - /path/to/dir | nc 10.240.30.3 5000
Launch remote shell
server> nc -l 5000 -e /bin/bash
client> nc 10.240.30.3 5000
Simple file server
while true ; do nc -l 5000 | tar -xvf - ; done
Simple minimal HTTP Server
while true ; do nc -l -p 1500 -c 'echo -e "HTTP/1.1 200 OK\n\n $(date)"' ; done
Simple HTTP Server
Restarts web server after each request - remove
while
condition for only single connection.
cat > index.html << __EOF__
<!doctype html>
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
<title></title>
<meta name="description" content="">
<meta name="viewport" content="width=device-width, initial-scale=1">
</head>
<body>
<p>
Hello! It's a site.
</p>
</body>
</html>
__EOF__
server> while : ; do \
(echo -ne "HTTP/1.1 200 OK\r\nContent-Length: $(wc -c <index.html)\r\n\r\n" ; cat index.html;) | \
nc -l -p 5000 \
; done
-p
- port number
Simple HTTP Proxy (single connection)
#!/usr/bin/env bash
if [[ $# != 2 ]] ; then
printf "%s\\n" \
"usage: ./nc-proxy listen-port bk_host:bk_port"
fi
_listen_port="$1"
_bk_host=$(echo "$2" | cut -d ":" -f1)
_bk_port=$(echo "$2" | cut -d ":" -f2)
printf " lport: %s\\nbk_host: %s\\nbk_port: %s\\n\\n" \
"$_listen_port" "$_bk_host" "$_bk_port"
_tmp=$(mktemp -d)
_back="$_tmp/pipe.back"
_sent="$_tmp/pipe.sent"
_recv="$_tmp/pipe.recv"
trap 'rm -rf "$_tmp"' EXIT
mkfifo -m 0600 "$_back" "$_sent" "$_recv"
sed "s/^/=> /" <"$_sent" &
sed "s/^/<= /" <"$_recv" &
nc -l -p "$_listen_port" <"$_back" | \
tee "$_sent" | \
nc "$_bk_host" "$_bk_port" | \
tee "$_recv" >"$_back"
server> chmod +x nc-proxy && ./nc-proxy 8080 192.168.252.10:8000
lport: 8080
bk_host: 192.168.252.10
bk_port: 8000
client> http -p h 10.240.30.3:8080
HTTP/1.1 200 OK
Accept-Ranges: bytes
Cache-Control: max-age=31536000
Content-Length: 2748
Content-Type: text/html; charset=utf-8
Date: Sun, 01 Jul 2018 20:12:08 GMT
Last-Modified: Sun, 01 Apr 2018 21:53:37 GMT
Create a single-use TCP or UDP proxy
### TCP -> TCP
nc -l -p 2000 -c "nc [ip|hostname] 3000"
### TCP -> UDP
nc -l -p 2000 -c "nc -u [ip|hostname] 3000"
### UDP -> UDP
nc -l -u -p 2000 -c "nc -u [ip|hostname] 3000"
### UDP -> TCP
nc -l -u -p 2000 -c "nc [ip|hostname] 3000"
Tool: socat
Testing remote connection to port
socat - TCP4:10.240.30.3:22
-
- standard input (STDIO)TCP4:<params>
- set tcp4 connection with specific params[hostname|ip]
- set hostname/ip[1-65535]
- set port number
Redirecting TCP-traffic to a UNIX domain socket under Linux
socat TCP-LISTEN:1234,bind=127.0.0.1,reuseaddr,fork,su=nobody,range=127.0.0.0/8 UNIX-CLIENT:/tmp/foo
TCP-LISTEN:<params>
- set tcp listen with specific params[1-65535]
- set port numberbind=[hostname|ip]
- set bind hostname/ipreuseaddr
- allows other sockets to bind to an addressfork
- keeps the parent process attempting to produce more connectionssu=nobody
- set userrange=[ip-range]
- ip range
UNIX-CLIENT:<params>
- communicates with the specified peer socketfilename
- define socket
Tool: lsof
Show process that use internet connection at the moment
lsof -P -i -n
Show process that use specific port number
lsof -i tcp:443
Lists all listening ports together with the PID of the associated process
lsof -Pan -i tcp -i udp
List all open ports and their owning executables
lsof -i -P | grep -i "listen"
Show all open ports
lsof -Pnl -i
Show open ports (LISTEN)
lsof -Pni4 | grep LISTEN | column -t
List all files opened by a particular command
lsof -c "process"
View user activity per directory
lsof -u username -a +D /etc
Show 10 Largest Open Files
lsof / | \
awk '{ if($7 > 1048576) print $7/1048576 "MB" " " $9 " " $1 }' | \
sort -n -u | tail | column -t
Tool: netstat
Graph # of connections for each hosts
netstat -an | \
grep ESTABLISHED | \
awk '{print $5}' | \
awk -F: '{print $1}' | \
grep -v -e '^[[:space:]]*$' | \
sort | uniq -c | \
awk '{ printf("%s\t%s\t",$2,$1) ; for (i = 0; i < $1; i++) {printf("*")}; print "" }'
Monitor open connections for specific port including listen, count and sort it per IP
watch "netstat -plan | grep :443 | awk {'print \$5'} | cut -d: -f 1 | sort | uniq -c | sort -nk 1"
Tool: rsync
Rsync remote data as root using sudo
rsync --rsync-path 'sudo rsync' username@hostname:/path/to/dir/ /local/
Tool: host
Resolves the domain name (using external dns server)
host google.com 9.9.9.9
Checks the domain administrator (SOA record)
host -t soa google.com 9.9.9.9
Tool: dig
Resolves the domain name (short output)
dig google.com +short
Lookup NS record for specific domain
dig @9.9.9.9 google.com NS
Query only answer section
dig google.com +nocomments +noquestion +noauthority +noadditional +nostats
Query ALL DNS Records
dig google.com ANY +noall +answer
DNS Reverse Look-up
dig -x 172.217.16.14 +short
Tool: network-other
Get all subnets for specific AS (Autonomous system)
AS="AS32934"
whois -h whois.radb.net -- "-i origin ${AS}" | \
grep "^route:" | \
cut -d ":" -f2 | \
sed -e 's/^[ \t]//' | \
sort -n -t . -k 1,1 -k 2,2 -k 3,3 -k 4,4 | \
cut -d ":" -f2 | \
sed -e 's/^[ \t]/allow /' | \
sed 's/$/;/' | \
sed 's/allow */subnet -> /g'
Resolves domain name from dns.google.com with curl and jq
_dname="google.com" ; curl -s "https://dns.google.com/resolve?name=${_dname}&type=A" | jq .
Tool: awk
Remove duplicate entries in a file without sorting
awk '!x[$0]++' filename
Exclude multiple columns using AWK
awk '{$1=$3=""}1' filename
Tool: sed
To print a specific line from a file
sed -n 10p /path/to/file
Remove a specific line from a file
sed -i 10d /path/to/file
# alternative (BSD): sed -i'' 10d /path/to/file
Remove a range of lines from a file
sed -i <file> -re '<start>,<end>d'
Tool: grep
Search for a "pattern" inside all files in the current directory
grep -rn "pattern"
grep -RnisI "pattern" *
fgrep "pattern" * -R
Remove blank lines from a file and save output to new file
grep . filename > newfilename
Except multiple patterns
grep -vE '(error|critical|warning)' filename
Show data from file without comments
grep -v ^[[:space:]]*# filename
Show data from file without comments and new lines
egrep -v '#|^$' filename