TIL

Today I Learned

Things I Learned today, found on Simon's Blog, and repo can be found here: Repo

190 TILs so far.

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Recently Added/Updated TILs

• Run MTR on MacOS without sudo

• Limit Upload Download Speeds in Rclone

• Fix Icons Not Displaying in Terminal

• Why All Users Can Write to /tmp

• Fix Clear Command Not Found

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Categories

• Linux

• Ansible

• Caddy

• Cheatsheets

• Docker

• Git

• Github

• Go

• Learning Resources

• MacOS

• Miscellaneous

• Python

• Rclone

• ReactJS

• Vagrant

• VSCode

• WSL

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Linux

• Add Swap Space To System

• Add User To System

• Beautify Logs

• Benchmark System

• Ccze Scrolling Output

• Change Default Shell

• Change Hostname Of A system

• Changing User Password In Shell Script

• Check Group Of A User

• Check If A Package Is Installed Or Not

• Check If A Port Is In Use

• Check If A User Exists

• Check Open Port

• CMake Parallel Build with All Cores

• Create Symbolic Links

• Determine Which Process Is Using a File

• Enable SSH Server

• Fix Permission For Newly Created Partitions

• Fix Windows And Linux Different Time Issue

• Get Arch Of System

• Increase Limit of Inotify Watchers

• Install Latest NodeJS In Linux

• Install Pavucontrol

• Install Postman

• Kill A Process In Linux

• Mount Partition On System Startup

• OpenVPN Server

• Ping over TCP

• Pipe Password to Sudo

• Remove PPA From System

• Remove User Password

• Root Check in Scripts

• Run Go Binaries Without Installing Go

• Set Different Time Zone

• Show Disk Usage By Directories

• Show Public IP

• Show Size of Current Directory

• System Ugprade

• Tar Exclude Directories

• Tar Retain File Permissions

• Why All Users Can Write to /tmp

Alpine Linux

• Adding User On Alpine

• Chaning Timezone On Alpine

• Installing Ansible On Alpine

• Installing Dig On Alpine

• Installing Pip On Alpine

• Installing Python2 On Alpine

Apt

• APT Fix Broken Packages

• APT Hold Packages From Upgrade

Arch Linux

• Install Docker Compose

• Install Docker

• Install Pip

Bash

• Bash List Only Directories

• BashTOP Resource Monitor

• Case Statements

• Concatenate Strings

• Custom Shell Prompt

• Length of String in Variable

• Test Regular Expression Against A String

• Pass Arguments while Piping

• Read Command Output In Reverse Order

• "set -e" In Scripts

• Set MacOS Like Terminal Font

• Set Unlimited Bash History

• Shell Formatter

• Yes

Curl

• Fix Failed Writing Body While Piping

• Use Proxy Server in cURL

Fedora

• Fix Clear Command Not Found

• Install RPM Packages in Fedora

GPG

• Fix "Inappropriate ioctl for device" Error

• GPG Import Keys

• GPG Test

• GPG Trust Key

• GPG Verify Signature

Grep

• Grep Case Insensitive Search

• Grep Count Occurance

• Grep Exact Match

• Grep Invert Search

• Grep On Continous Stream

• Grep Quiet Mode

• Grep Search For Multiple Strings

• Remove Empty Lines

Journalctl

• Get Errors in Running Services using Journalctl

Networking

• Install Dig

• Install MTR

• Set Metric For A Network Using nmcli

• WireGuard Server

Raspberry Pi

• Disable Swap Memory on SD Card

SSH

• Reconnect To a Disconnected SSH Session

• Run A Local Script On Remote SSH Server

• Screen

• Tmux

Systemd

• Create A Service

• Create A Systemd Timer

• List Systemd Services Of A User

• Prevent Systemd Timers From Overlapping

• Watch Systemd Service Status

Tcpdump

• Capture ICMP Packets

• Capture Traffic By IP Or A Network

Ubuntu Linux

• Get Clipboard History

• Install HMAC256 On Ubuntu

• Obtaining a List of Ubuntu Repository Mirror Servers

Wget

• Basic Authentication

Ansible

• Add Authorized SSH Key to User using Ansible

• Ansible Add User to System

• Ansible Configure Default Inventory File

• Ansible Disable Python Interpreter Warnings

• Ansible Pause Playbook Execution

• Ansible Test Connection

• Run Ansible Playbook Locally

• Setting a Password in Ansible Inventory File

Caddy Server

• Caddy Write Logs to a File

• Return Client IP Address As Plain Text

Cheatsheets

• Bash Cheatsheet

• Grep Cheatsheet

• Markdown Cheatsheet

• MongoDB Cheatsheet

• Networking Cheatsheet

• Python Cheatsheet

• ReactJS Cheatsheet

• Regex Cheatsheet

Docker

• Docker Build Multiple Tags At Once

• Docker Exec

• Docker Publish Port

• Docker Run Without Cache

• Docker Run

• Fix UFW Security Flaw

• Install Docker

• Install Ping in Docker

• Pass Build Time Arguments To Docker Build

• Remove Container When It Exits

• Remove Unused Data

• Run Docker without root

• Setup Docker Buildx For Multi Arch Builds

Git

• Change Last Commit Message

• Delete Tag

• Get Tag Names in Git

• Save Credentials for Remotes in Git

• Show Commit Only From One Author

• View Git Commit Changes

GitHub

GitHub Actions

• Setting An Environment Variable

• Running Jobs in a Container

Go

• Convert String To Uppercase in Go

• List All Possible GOOS And GOARCH

• Print Go Version

• Resolve Hostname To IP Address

• Trim Whitespaces From String

• Update Project Libraries To Latest

Learning Resources

• Algorithms

• DevOps

• Git

• Linux

• Networking

• Programming Languages

MacOS

• Run MTR without sudo

Miscellaneous

• Good Reads

• Must Read Sites

• Useful Sites

Python

• Add An Item To Dictionary

• Check If A Key Exists In Dictionary

• Check If a String is Empty

• Check Image Size

• Check Python Version Programmatically

• Convert List To Tuple

• Execute Python Code in Command Shell

• Formatted Strings

• Get IP Address From Hostname

• Limit Floating Point To Two Decimal Places

• Measure Latency Using TCP

• Pass List as Argument to a Function

• Print Tabular Data

• Python Padding Strings

• Read A File Line By Line

• Remove A File

• Remove Trailing Spaces And New Lines From A String

• Run Python Script in Background

• Split String with Delimiter

• Validate IP Address

Pipenv

• Install Dependencies System Wide

• Remove Virtualenv

Rclone

• Limit Upload Download Speeds in Rclone

ReactJS

• ReactJS Resources

Vagrant

• Increase RAM And CPU On Vagrant Machine

• Vagrant Specify Disk Size

VSCode

• Fix Icons Not Displaying in Terminal

• Install VS Code on a Linux Server

WSL

• Convert WSL1 to WSL2

• Enable Systemd Support in WSL2