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Install ZooKeeper in Distributed Mode for Hadoop
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Hadoop
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Hadoop 2.6.3 dynamically add/remove DataNode
Hadoop HDFS HA show two StandBy NameNode
Hadoop Interview Questions and Answers
Hadoop Default Port and Usage
Hadoop Secondary Namenode
Install Hadoop 2.6.3 cluster on CentOS 6.7
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CDN
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CDN providers - Comparison & Summary
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Cloud
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CloudNative
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CloudService
Top 25 Cloud Service Providers
[MultiCloud] Create internal connection between AWS and Azure with IP-VPN
AWS
AWS
Use AWS S3 as static website
use lambda to handle S3 cross region replication on AWS
Set AWS S3 bucket permission with mc tool
Introduce to system damage level
Visit self-host AWS s3 service with aws cli
Azure
Azure
Add reverse DNS record for public ip in Azure
OracleCloud
OracleCloud
Disable Ubuntu default firewall on Oracle Cloud
Enable ipv6 for instances on Oracle Cloud
Kubernetes
Kubernetes
Kubernetes Basics
Kubernetes components overview
How to Create a Secret Volume in Kubernetes
Creating an Amazon EKS cluster
Kubernetes Installer Tools
Kubernetes Pros and Cons
Linux Kernel Tuning for Kubernetes
Essential Troubleshooting Manual for Kubernetes
Pod stuck in Terminating state
Enterprise Kubernetes Management with Rancher
Managed Kubernetes Services
Usage of helm
Troubleshooting K8s Issues from 9 aspects
Usage of kubectl
Usage of configmap
Usage of daemonset
Usage of deployment/replicaset
Connect to a Specified Container When a Pod Has More Than One Container in k8s
Usage of jobs
Usage of StatefulSets
Security Tips for Kubernetes
How to setup ArgoCD from scratch and deploy your app
Install & setup Kubernetes cluster from scratch on Ubuntu
Workflows on Kubernetes
Container
Container
Container Basics
Buildah Basics
Buildpacks Basics
Calico Basics
DevPod Basics
Building a Container with Jib
OCI Runtimes - Basics
Skopeo Basics
Colima
Colima
Colima - container runtimes on MacOS
Crictl
Crictl
Container Runtime Interface (CRI) CLI - crictl
Docker
Docker
Docker Cheat Sheet
Management of Docker Containers Network
Manage Docker Containers Volume and Environment
Creating and Managing Container Images
Podman
Podman
Podman Cheat Sheet
Podman pull official images from docker hub
PouchContainer
PouchContainer
PouchContainer
Snaps
Snaps
Usage of Snap on Ubuntu
DNS
DNS
What is DNS
Cloud DNS Route Policy and its Application
CoreDNS - A Flexible and Powerful DNS Server
How to CNAME root domain and alternative solution
Usage of dig command
Public DNS over TLS
Verify the authenticity of DNS records with DNSSEC resolver delv
How to find subdomain from given domain
Understanding Multicast DNS (mDNS)
Name.com coupon list
Public Free DNS Service
What is HSTS
Database
Database
How to configure SSL/TLS for MySQL on Linux
How To Create and Manage PostgreSQL Databases
Introduction to ID generation method
SQL Cheat Sheet
Recommended Linux Kernel and System Settings for PostgreSQL
30 Minutes PostgreSQL Tutorial
SQL Interview Questions Cheat Sheet
Backup Mysql with ssh & mysqldump
Database Fundamentals
Deploy PostgreSQL With Docker
How to Reset MySQL Root Password
Debug
Debug
What is Debug
Selenium
Debug in bash
What is Bugzilla
Calico verbose panic log: ip6tables-legacy-save failed
Debugging C with Clang compiler and LLDB on MacOS
Debug in Go
Find C/C++ memory leak with valgrind in Linux
Debug & Analyzing coredump with gdb
Debug in Lua
Network packets debug with tcpdump
How to debug if No Shell for Your Container
Debug in Python3
DevOps
DevOps
DevOps - Basics
ChatOps
Jira
Apache Maven
Puppet
StaltStack
SonarQube
Splunk
Server Management Tools
Efficient CLI Tools for DevOps
DevOps workflow
Opensource Project Management Tools
pssh
CICD
CICD
What is CI/CD
ArgoCD
Bitbucket CI
CircleCI
FluxCD
Kargo
Travis-CI
CI/CD Workflow
Deploy static web to GitHub pages with GitHub Action
CI/CD Products and Solutions
CMDB
CMDB
Summary of CMDB system
IaC
IaC
Infrastructure as Code (IaC)
AWS Cloud Formation
Create AWS ECR Repository with Terraform
Terraform
Import existing AWS resources to terraform
Jenkins
Jenkins
Jenkins
Frequently used Jenkins plugins
Implement Jenkins HA
Store multiline string parameter into file in Jenkins
Jenkins RestAPI call with Error 403 No valid crumb was included in the request
Jenkins REST API Usage Example
Ansible
Ansible
Ansible Basics
Ansible ad hoc command examples
DevSecOps
DevSecOps
What is DevSecOps
10 Best Free SSL Checker Tools for Troubleshooting and Analysis
Firewall checklist and cyber security tools
Modern Cybersecurity Strategies for Enterprises
Nessus: The Ultimate Vulnerability Scanner
Using Google Authenticator for SSH
One-time password (OTP) implementation in Shell, Python and Go
Summary of implementation of TLS/SSL protocol
Sign/Validate files with gpg
What is Identity and Access Management (IAM)
nmap usage cheat sheet - Network Mapper
How to kick out inactive user on Linux
Check last successful/failed login user in Linux
Calculate last failed login user with source ip in Linux
Vulnerability and bug scan in Linux
Privilege escalation misconfigurations check for Linux
nich - quickly analyze open ports vulnerabilities
OpenSSL Cheatsheet
Private Search Engines
Security tips for developers
Security tips when using VPN
How to Sign/Verify files with SSH
How to get ssh public key from private key
usage of tunnels and proxies in SSH
Types of VPN
Distributed System
Distributed System
Distributed Systems - what should be considered
BASE
CAP
Paxos
Gossip
Raft
Engineering
Engineering
Understanding Chaos Engineering
Latency and CPU speed infomation
Prompt Engineering
Engineering Book Recommendations
RSS List of Technical Engineering Blogs
Summary of IT engineering blogs
Mail service with custom domain
RSS Reader & Service
Elastic Search Alternatives
Interview
Interview
Coding Interview Advice
The 24 Hours Before Your Interview
How To Get The Most Out Of Your Coding Interview
Tricks For Getting Unstuck During a Coding Interview
FinOps
FinOps
What is FinOps
AWS Cost Optimization Basics
Fun
Fun
Hands-on Generate your own AI QR code online in 30 Minutes
Hands-on ChatBot
Man Page Cheat Sheet
RAID Capacity Calculator
Funny command line browser Lynx
How to Set Up Custom Domain for Sending Emails in Gmail
Get all pages title and url in Notion API
GitHub funny resource
How to Download Chrome Offline Installer
Useful Icon Search Website Summary
Regular Expressions Cheat Sheet
Advanced Operators in Search Engine at a Glance
Static blog generator summary
Vim CheatSheet
Easter eggs in vim
Vim Hotkey cheetsheet
Vim Reference Summary
Save file in vim with permission denied
vimrc recommended setting
When Cloudflare unavailable
When DBS App unavailable
When GitHub unavailable
When Google unavailable
When LinkedIn App unavailable
When Stack Overflow unavailable
zero-width space
Gateway
Gateway
Traefik
APISIX
GitOps
GitOps
What is GitOps
GitOps: Streamlining Your Software Development Lifecycle
Mercurial
Bitbucket: A Comprehensive Guide
Git Cheat Sheet
delete untracked files with git clean
Git GUI Client Recommendation
Understanding SVN: A Version Control System
Use ssh to connect git repo on GitHub
YAML Basics
Go
Go
Golang - Basics & Cheatsheet
8 Ways to Use Colon in Go
What is Context in Golang
Getting Started with HTMX and Go
Running Background jobs with gocraft in Golang
Effective Go tips and notes
Add version info in your Go project
Benchmark with examples in Go
Go 1.18 on MacOS: linkname must refer to declared function or variable
Makefile example in golang
Read and Set Environment variables in Go
Using Redis in Go - Example and Demo
WaitGroup example in Go
Channel based concurrency in Go
Clear terminal screen/console in Golang
Reduce binary file size in Golang
An Implementation of random.shuffle in golang
Web shell in golang
Learning Go - Summary of Golang learning material
Groovy
Groovy
Introduction to Groovy
Groovy Cheat Sheet
HTTP SSL
HTTP SSL
What is HTTP SSL/TLS
What is WebSockets
/usr/bin/curl: Argument list too long
Ignore invalid and self signed SSL check in curl and wget
How to download the whole website in one command
How to get free IP SSL certificate in 30 minutes
SSL/TLS
GUI HTTP Debug and API testing Tools
Cross platform HTTP/S benchmark tool - Cassowary
Introduction to QUIC
Using curl to output detail time consuming of http
Realtime web benchmark tool on CLI
Use Nginx as forwarding proxy
Use Nginx as reverse proxy for WebSocket
How to Convert Socks5 Proxy to HTTP Proxy
Introduction to SSL Pinning
Remove password for a password protected SSL private key
Summary of web framework in different language
Command Line HTTP Browser
Java
Java
How to Dockerize Java Application
High Concurrency System Design 40 Questions
JBoss: An Introduction and Usage
Resin Java EE Application Server
Linux
Linux
Reading List
How to find out all Kernel Boot Parameters
Apparmor conflicted with ntpd: apparmor=DENIED operation=capable
How to delete file: Argument list too long in Linux
awk command cheat sheet
Run process in background on Linux
How to calculate TCP connection infomation without ss and netstat
How to change Linux hostname
How to change Timezone in Linux with timedatectl
How to lock important files in Linux
How to calculate md5, sha1, sha256, sha512 checksum in Linux
How to clean up penetration trace
The most frequently used performance check commands in Linux
Hotkey with Ctrl in Linux
Use crontab and flock to control cron job sequence
How to delete specific files EXCEPT the certain pattern
Summary of File and Directory permission - rwxst
How to get disk block size in Linux
How to Get Hardware and Temperature Information from Terminal
Basic usage of dstat
Why disk space not change after remove large files in Linux
Basic usage of find command in Linux
How to fix nf_conntrack: table full, dropping packet
Enable and Disable Ping in Linux
How to generate random hexadecimal in Linux
Basic usage of grep command
How to read and open hex file in Linux
How to Use Iptarf to Monitor Network Traffic and Bandwidth
Useful resources for Linux kernel development
Detail usage of ls -l command
How to Find out Open Files for a Given PID or Process
Tune and change max open files limit in Linux
mosh - UDP based SSH tool in Linux
One time file transfer with nc command
Linux disk visualization tool - ncdu
How to fix Linux kernel: neighbour table overflow
Summary of network related commands in Linux
Usage of Netstat Command in Linux
Top 20 Linux system performance tools
Linux POSIX character set
Deep look at Linux process state
Purge file system cache in Linux
How to specify SSH port in rsync command
Basic usage of scp command
Basic usage of sed command
What is SetUID、SetGID and Sticky bit
TCP/UDP port forwarding with socat
TCP/UDP port forward with socat
How to Add Files to Linux Path
How to fix ssh connection: POSSIBLE BREAK-IN ATTEMPT
How to extend syslog max length per line in Ubuntu 20.04
Basic usage of tar command to (de)compress gz/bz2/xz files
tmux hotkey cheatsheet
How to solve too many TCP connections in Linux
How to trigger a kernel panic & generate a coredump file in Linux
How to ignore case sensitive characters in ls command
Comparison of different NTP Services
Basic usage of rsync Command
How to subscribe Linux Kernel Mail List
Config and add PATH in supervisor
Understand cgroups - demo and explanation
Understand Systemd - demo and explanation
What is Linux AppArmor
Why should we forbid THP and How to do it
LoadBalance
LoadBalance
What is Load Balance
What is Reverse Proxy, API Gateway, Load Balancer
A high availability (HA) network gateway using Keepalived and Nginx
What is Haproxy
What is Keepalived
Optimize and tune Nginx for high concurrency
Usage of Nginx module http_stub_status_module
Nginx supported signal list
HTTP Load Balancing with Nginx
Lua
Lua
What is Lua
What is OpenResty
Implement WAF rules with LuaJIT - Demo and examples
MQ
MQ
Message Queue
RabbitMQ
Apache Pulsar
Kafka
Kafka
Kafka - Introduction
Kafka Basics
Network
Network
Network Basics
BGP Basics
FRP Fast Reverse Proxy - Basics
NAT Basics
OSPF Basics
TCP Acceleration Basics
Summary of Tunnel Forwarding Tools
VPC and Subnet
Count connections by TCP state
CIDR calculator
Container Network Interface (CNI) Basics
Get public IP with 1 line curl command
iptables - basics
Get Ping result from multiple location
Port based speed limit/traffic control in Linux
Optimize TCP_NODELAY
tcp_moderate_rcvbuf basics
TCP State Basics
TCP window-size scaling
Tcpdump parse with Wireshark
Troubleshoot Pod Networking Issues using nsenter
NoSQL
NoSQL
NoSQL Basics
Codis
Introduction to gossip
NoSQL system summary and comparison
Search services & tools
CAP theory in NoSQL
Cassandra
Cassandra
Cassandra Basics - Performance Tunning
Deploy Cassandra with ccm
Manage Cassandra with nodetool
MongoDB
MongoDB
MongoDB Performance Optimization cheat sheet
How to Setup MongoDB Replication On Ubuntu 20.04
MongoDB Shell - Basics
MongoDB Basics - Monitoring
Redis
Redis
Redis - Basics and summary
Aliyun Redis best practice
Change and Save Redis configuration during running
From 0 to 1 - create Redis cluster
parse and decode Redis AOF file with Python
Commands for Redis clients
Useful cluster commands for Redis Cluster
Redis compatible NoSQL system performance comparison
Redis config file explaination and reference
Redis source code - how to get started
Redis Memory Usage Explanation
Redis Optimization Cheatsheet
Redis persistence Explanation - RDB and AOF
Redis rebalance - slot migration process
Redis source code files description
Summary of Redis Tips and Tricks
RocksDB
RocksDB
RocksDB
RocksDB Administration and Data Access Tool
RocksDB Reference
ZooKeeper
ZooKeeper
Introduction to Zookeeper
Etcd
Etcd
Backup/Restore ETCD for Kubernetes
OLAP
OLAP
OLAP Basics
OS
OS
Operating System (OS)
ArchLinux
ArchLinux
Pacman: Package management on Arch Linux
CentOS
CentOS
How to apply for Wildcard Certificate on CentOS
How to add user into admin group on CentOS
How to use web benchmark tools on CentOS
How to config nginx to support SSL/TLS on CentOS
How to hide nginx version on CentOS
How to compile nginx-1.13.10 to support http/2 on CentOS 7
How to use nsenter on CentOS
How to install different version of gcc 4.8/4.9/5.2 on CentOS 6
How to add SWAP partition on CentOS
How to add extanded repo on CentOS
How to send email using sendmail on CentOS
How to Change Timezone on CentOS
How to find out which package provide command/so on CentOS
Install and Configure BT Transmission on CentOS
How to fix iostat command cannot found on CentOS
How to fix mkfs.xfs command not found on CentOS
Configure load balance using Nginx 1.8 on CentOS 6.7
Debian Ubuntu
Debian Ubuntu
Install AnyConnect compatible VPN Ocserv on Debian
Install OpenVPN on Debian 11
Configure BBR on Debian and Ubuntu
Extract files and content from deb package
How to remove welcome message after SSH login in Ubuntu
Simple Systemd User Service Example
Disable ipv6 on Ubuntu 20.04
Disable snap/snapd on Ubuntu 20.04 and later
Install sar error: Please check if data collecting is enabled
Upgrade debian 10 to debian 11
FreeBSD
FreeBSD
Useful FreeBSD commands & cheat sheet
Alternative Linux commands on FreeBSD
Build your own kernel of FreeBSD
Change csh to bash on FreeBSD
Configure FreeBSD to forbid ping (ICMP)
FreeBSD git repo
Install ocserv on FreeBSD
FreeBSD system update and package installation
Upgrade To FreeBSD 13 From FreeBSD 12
MacOS
MacOS
How to delete all .DS_Store files on MacOS
Disable brew analytics on MacOS
signing and notarizing CLI binaries on MacOS
netstat command on MacOS
Disable Chrome auto update on MacOS
Clean system log on MacOS
MacOS development environment essential list
Get a plain text of man page without backspaces and underscores on MacOS and BSD
Mac iTerm2 login CentOS warning: setlocale: LC_CTYPE: cannot change locale (UTF-8): No such file or directory
MacOS Sublime Text Vim mode continuously press
MacOS uninstall Jenkins
SUSE
SUSE
OpenSUSE package management tool - Zypper
Observability
Observability
Observability Basics
What is eBPF
APM
APM
What is APM? - Application Performance Monitoring Basics
Logging
Logging
Logging
Linux Log Types and Usage
Sentry
Vector: high-performance data pipeline
Monitoring
Monitoring
Monitoring
CloudWatch
Customize your status page with CloudFlare Worker and Atlassian Status Page
Website Health Check with Cloudflare Worker
Modern Monitoring System
Zabbix
Prometheus
Prometheus
Prometheus Basics
Datadog
Datadog
DataDog Basics
Grafana
Grafana
Grafana
Grafana Cloud Basics
Influxdb
Influxdb
InfluxDB Basics
Openfalcon
Openfalcon
Open-Falcon Basics
Tracing
Tracing
Tracing
Dynatrace
MantisBT
OpenTelemetry
SkyWalking
PHP
PHP
What is PHP
How to call Python in PHP code
How to compile and install PHP 5.6 on CentOS 6.x
How to install phpMyAdmin on CentOS with LNMP
PHP configure: error: mcrypt.h not found. Please reinstall libmcrypt
PHP 5.6 start failed to open configuration file /usr/local/php/etc/php-fpm.conf
Performance
Performance
Performance Tuning
InnoDB Performance Optimization Basics
Ceph Performance Tuning Suggestions
Performance checkpoints for Linux Optimization
Linux kernel parameter - memory dirty page
Enable/Disable high resolution timers in Linux
Linux kernel parameters - network
Linux kernel parameters optimization
Check Linux kernel parameter from proc
Performance monitor and tracing command in Linux
USE Method: Linux Performance Checklist
CPU/MEM/IO benchmark and performance test with sysbench
Web Servers Load Testing with Siege
Optimize MySQL for 256MB or small memory VPS
Tuning Linux I/O Scheduler for SSDs
Perl
Perl
What is Perl
How to clear terminal screen in Perl
Platform
Platform
Jump Server
SRE Works
Python
Python
What is Python
19 Python Syntax Sugars - demo & example
Django Cheat Sheet
master Python3
implement lru cache in Python
Using Python socket to get public address
Send http/https requests with Python
Introduction to Python PEP8
Accelerate Python Function with Numba
Python bisect module demo
Catch signal in Python
How to clear screen (console) in Python3
common package and module in Python
Python asynchronous programming demo: process/thread pool
Using datetime to Deal with Time in Python
currency calculation using decimal in Python
Python decorators usage and example
3 ways to set timeout on function call in Python
8 ways to use functools with examples in Python
Get local IP address with Python
What is GIL in Python and examples
Iterate over multiple lists (tuple) simultaneously in Python
List, dictionary, set comprehension in Python
3 Ways to disable output buffer when running Python
Two methods for fast pairing lists in Python
Python performance analysis with Profile module
Python Project Structure: Best Practices
usage of virtualenv in Python
Program in Pythonic way
Python: question list
single and double underscore of class member name in Python
dict sort in Python based on key, value
try except else finally in Python
Multithread Efficiency Comparison between Python and PyPy
Start a new Python3 Environment in 10 sececond
Set Multiple CORS Domains in Flask
Where is your installed Python packages?
QA
QA
Difference Between Amazon EBS and Amazon EFS
Ruby
Ruby
Docked Rails CLI
Easiest way to build your own Ruby on MacOS
How to Start Ruby on Rails on MacOS
Ruby Cheatsheet
Rust
Rust
Rust Cheat Sheet
Clear terminal screen/console in Rust
SRE
SRE
Site Reliability Engineering
Disaster Recovery
Cloud Migration
Platform Engineering
SRE at a glance
SLA, SLO, and SLI
SRE A Comprehensive Guide
SRE Terminology
Handover Checklist from Dev team to SRE team
Cloud Service SLA
Chaos Scenario Checklist
Status Page Summary
Chaos
Chaos
First Head Chaos Engineering
Serverless
Serverless
What is Serverless
Shell
Shell
What is Shell
Top 300 shell commands
How to delete files with space characters in file name
What is Fish Shell
Get the union, intersection, difference between 2 files with sort and uniq
How to extract multi segments of a json file and merge them into 1 line with jq
LeetCode one-liner bash script problems and answers
How to check current shell in Linux
How to forbid output redirection to avoid overwrite the existing file
Alternative of grep command
How to repeat lastest command/arguments in Bash with the help of !
How to create and write a file with EOF in Bash
Reverse Shell
Environment variable in csh, tcsh, bash, zsh
change stdout with ANSI character set
How to decompress password protected zip file on MacOS/Linux Terminal
Bash
Bash
Linux bash cheatsheet
Disable Output Redirect in Bash
Linux bash cheatsheet
Special characters in Bash
Concurrency Control in Bash Programming - demo and example
Bash Scripting
Arithmetic operation in Bash
Use array in Bash
Getting file names from paths with Bash script
Concurrency programming in bash script with timeout control
How to Debug in Bash Script
Detach foreground process from terminal in Linux
Usage of $ sign in Bash Scripting
Detect whether the file exists or not with Bash
Bash Functions: How to Create and Use Them
Detect whether current user is root in Bash
Remove color codes from output with sed in Linux bash
Variable Replacement and Truncate in Bash Command Line
Different types of user switch in Linux
test statement in bash programming
Summary of different types of variables in Bash
Different loop style in Bash
Zsh
Zsh
How to clear command history in zsh
System
System
Systems Design in real world
Payment Systems Basics
TLDR
TLDR
Read CPU model specific registers
Bash Scripting Examples
Compact jq output/result in 1 line
Install Cassandra on Ubuntu 22.04
Manage multiple SSH key for github and gitlab
Tips
Tips
Tools and Tips
How to Use ssh-agent
How to create a HAproxy Load Balancer with floating IP
Add a dir to PATH
How to List Cron Jobs
Linux System Monitoring
How to Use ack Command
How to Use ag Command
How to Use rm Command
How to Use bat Command
How to Use bottom Command
How to Use broot Command
How to Use cat Command
How to Use cheat Command
How to Use chmod Command
How to Use choose Command
How to Use chroot
How to Use curlie
How to Use date Command
How to Use dog Command
How to Use e2fsck Command
How to Use echo Command
How to Use ffmpeg Command
How to Use find Command
How to Use fsck Command
How to Use glances monitoring
How to Use gping Command
How to Use gtop Command
How to Use head Command
How to Use HTTPie
How to Use Hurl Command
How to Use hyperfine
How to Use journalctl Command
How to Use jq Command
How to Use kill Command
How to Use head Command
How to Use logrotate Command
How to Use lsmod, modinfo
How to Use mongodump
How to Use mount Command
How to Use mysqldump
How to Use nslookup
How to Use procs Command
How to Use ps Command
How to Use rclone Command
How to Use ripgrep
How to Use rm Command
How to Use rsync Command
How to Use scp
How to Use sd Command
How to Use sed Command
How to Use SELinux
How to Use sort uniq
How to Use ssh tunnel
How to Use systemctl
How to Use tail Command
How to Use tar Command
How to Use tar Command
How to Use tcpdump
How to Use tldr Command
How to Use xargs Command
How to use ping Command
Load Testing with Siege
ZeroTrust
ZeroTrust
What is Zero Trust
Zero Trust Architecture
Payment Systems Basics
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