- Introduction
- Operating System
- Linux Boot Process
- Filesystems
- RAID
- IPC
- Sockets
- RPC
- Signals
- POSIX signals
- Threads
- Streams
- Caching
- Scheduler
- Write-through, write-around, write-back: Cache explained
- Tempfiles
- System Calls
- PID Definition
- Shared Memory
- Zombie process
- What's in an inode?
- What are the common run levels in linux
- What is the difference between soft and hard links
- What happens when a process forks?
- How-To Compile Linux Kernel from Source
- Understanding Sticky-Bit, SUID and SGID in Linux
- Understanding User and Kernel Mode
- Understanding Linux CPU Load - when should you be worried?
- Kernel namespaces
- Control groups
- Stack vs Heap
- What is the difference between a process and a thread
- The Differences Between MBR and GPT
- Fork
- Exec
- How Linux actually handles fork and exec
- PROC
- Error Detection & Correction
- limits.conf
- PXE Boot
- Anatomy of the initrd and vmlinuz
- Buffer and Cache
- Unix time
- Networking
- TCP connection
- What is SYN Flood, ICMP Flood
- How does DNS server work
- Hubs vs Switches vs Routers – Networking Device Fundamentals
- TCP/IP Protocol Fundamentals Explained with a Diagram
- OSI MODEL
- Journey of a Data Packet in the Internet
- Introduction to Linux IP Routing Fundamentals
- Virtual Local Area Network (VLAN)
- What is the difference between UDP and TCP internet protocols?
- SMTP, a simple socket protocol
- POP3, the Post Office Protocol
- IMAP, the Internet Message Access Protocol
- How to subnet: Subnetting calculations and shortcuts
- HTTP Status Code
- How does HTTPS actually work?
- What is SSL and what are Certificates?
- CIDR (Classless InterDomain Routing)
- Address Resolution Protocol (ARP) definition
- Egress traffic
- Ingress traffic
- NAT - Network Address Translation
- UDP Services
- HTTP with Non-Persistent Connections
- HTTP with Persistent Connections
- How SMTP work
- How DNS work
- When do DNS queries use TCP instead of UDP?
- A Day in the Life of a Web Page Request
- CDN Operation
- Network/Subnet splitting
- TCP Connection Termination
- Ethernet Bonding modes
- EtherChannel Switch Link Aggregation
- Broadcast Address Definition
- Tshark
- Programming Language
- Python
- Time Format
- Subprocess
- Multiprocess
- Rename
- SMTP
- Single instance of program
- Argparse
- Requests
- Pyinstaller
- Readlines
- Raw Input
- With Open
- Configparser
- Gzip
- Listdir
- Basename
- Dirname
- Traversing a Directory Tree
- Startswith
- Endswith
- Virtualenv
- Regular Expressions
- Supervisor
- Socket
- Exception Errors
- Raw_input
- Threading
- Unittest
- Why is it better to use “#!/usr/bin/env NAME” instead of “#!/path/to/NAME” as my shebang?
- OS
- Decorator
- String Formatting
- SimplePrograms
- 'all', 'any' are Python built-ins
- TemporaryFile
- How to capture stdout in real-time with Python
- Python simple techniques and common reference
- python reference fragments
- getpass
- Method overriding in Python
- Multiple levels of 'collection.defaultdict' in Python
- String Format
- Logging
- Convert Unicode Object to Python Dict
- The dir( ) Function
- Python dictionary has_key() Method
- glob – Filename pattern matching
- Lambda, filter, reduce and map
- doctest – Testing through documentation
- Load Python code dynamically
- Map, Reduce, Zip, Filter
- DICTIONARY COMPREHENSION
- Golang
- Bash
- Regex
- .bash_profile vs .bashrc
- EXPORT
- Scripts
- Change default shell
- Useful Bash Shell Built-in Commands
- Debug
- The standard filedescriptors
- Exit codes
- Special Variables
- Small getopts tutorial
- How rapid detection of base script syntax errors, it does not execute the script
- Write message to a syslog / log file
- Java
- Python
- Linux Command Line Tool
- Basic
- DIFF
- AC
- AWK
- CHMOD
- NMAP
- NETSTAT
- Flock
- Traceroute
- FIND
- GREP
- Crontab
- Kill
- SED
- CUT
- CURL
- IFCONFIG
- TCPDUMP
- TAR
- LSOF
- SORT
- Xargs
- Iptables
- xargs vs. exec {}
- Hdparm
- UNIQ
- STAT
- Execute Commands in the Background
- TAIL
- WGET
- Date
- FDISK
- Mount
- Make SWAP File
- Create a New User
- Create a New Group
- Setup SSH Passwordless Login in OpenSSH
- Parted
- RSYNC
- YUM
- RPM
- APT
- Install from Source
- Log Rotate
- FREE
- DF
- DU
- Sysctl
- NICE
- Renice
- PS
- DD
- BC
- LDD
- getcap, setcap and file capabilities
- Linux_Basename
- PMAP
- Alternative
- Readlink
- logrotate
- PIDOF
- Dmidecode
- lshw
- printenv
- SS
- w
- Strace
- pstree
- USERMOD
- ltrace
- ethtool
- IP
- Sar
- nethogs
- zip
- FPM
- getent
- ipmitool
- Building RPMs
- Megacli
- RKhunter
- fping
- blkid
- FSCK
- Package Manager
- mktemp
- ls
- Comm
- taskset
- fio
- tree
- ARP
- lsblk
- Security
- Virtualization
- Docker
- Expose Docker Remote API on CentOS
- The 15 Commands
- The Next 15 Docker Commands
- Automation is the Word Using DockerFile!
- Docker Registry & Workflows
- Ultimate Guide for Docker APIs
- Docker Remote API Commands for Images
- EXPORT AND IMPORT A DOCKER IMAGE BETWEEN NODES
- Time zone Docker vessel problems
- Distinction between Docker's Save and Export
- Simple Docker
- Docker Cheat Sheet
- Xen
- KVM
- Docker
- How-To
- CentOS: nf_conntrack: table full, dropping packet
- How To Fix “Error: database disk image is malformed” On CentOS / Fedora
- Finding the PID of the process using a specific port?
- How-To create hashed SSH password
- How to display and kill zombie processes
- Shell command to bulk change file extensions in a directory (Linux)
- 8 Powerful Awk Built-in Variables – FS, OFS, RS, ORS, NR, NF, FILENAME, FNR
- Changing the Time Zone
- HOW DO I DISABLE SSH LOGIN FOR THE ROOT USER?
- How-To rename the extension for a batch of files?
- How-To disable IPv6 on RHEL6 / CentOS 6 / etc
- How to clear the ARP cache on Linux?
- How-To crontab running as a specific user
- Ansible – exclude host from playbook execution
- HOWTO: Use Wireshark over SSH
- How-To Change Network Interface Name
- How-To Creating a Partition Size Larger Than 2TB
- Hot-To Linux Hard Disk Format Command
- Hadoop Troubleshooting
- Hive Troubleshooting
- HowTo Set up hostbased authentication for passphraseless SSH communication.
- Difference between a cold and warm reboot
- ls -l explained
- df falsely showing 100 per cent disk usage
- FSCK explained
- Manually generate password for /etc/shadow
- How To Change Timezone on a CentOS 6 and 7
- Setting ssh private key forwarding
- Persist keys in ssh-agent on OS X
- SSH Essentials: Working with SSH Servers, Clients, and Keys
- How to Change JVM Heap Setting (-Xms -Xmx) of Tomcat – Configure setenv.sh file – Run catalina.sh
- SSH ProxyCommand example: Going through one host to reach another server
- How to get Linux's TCP state statistics
- Linux TCP retransmission rate calculation
- How to determine OOM
- How-to check Java process heapsize
- Troubleshooting network issues
- How to check what sudo acces a user has?
- How to copy your key to a remote server?
- Linux date and Unix timstamp conversion
- SSH client personalized configuration
- How to Error Detection and Correction
- How To Kerberos
- How to identify defective DIMM from EDAC error on Linux
- Howto Install and Configure Cobbler on Centos 6
- How To Use GPG to Encrypt and Sign Messages on an Ubuntu 12.04 VPS
- HowTo: Debug Crashed Linux Application Core Files Like A Pro
- Create init script in CentOS 6
- Linux Change Disk Label Name on EXT2 / EXT3 / EXT4 File Systems
- How to retrieve and change partition's UUID Universally Unique Identifier on linux
- Using Text-Mode Serial Console Redirection
- How to Write Linux Init Scripts Based on LSB Init Standard
- How to create a Debian package
- How to create a RPM Package
- How to solve EDAC DIMM CE Error
- How to solve fsck.ext4: Unable to resolve UUID/LABEL
- How to expand an existing LSI raid array using MegaCli
- How to change user GID and UID in Ubuntu
- How to read a segfault kernel log message
- How to add cron job via command line
- How to restrict process CPU usage using nice, cpulimit, and cgroups
- Storage
- Monitoring
- Database
- Algorithm
- Software Engineering
- Data Structure
- Service
- Cloud-Init
- Kubernetes
- ETCD
- RESTful API HTTP methods
- Web cache
- Mesos
- ELK
- Cassandra
- Hadoop
- Hadoop Safe Mode
- Common hadoop command
- Hadoop How to Kill all the specified user Job
- Hadoop view local Sequencefile file
- Identify the most CPU-intensive jobs hadooop
- Understanding hadoop fsck, fs -dus, -count -q size output
- hadoop Management Command --dfsadmin
- Running DFSIO mapreduce benchmark test
- Quick Apache Hadoop Admin Command Reference Examples
- TeraSort benchmark suite
- NameNode benchmark (nnbench)
- MapReduce benchmark (mrbench)
- Hadoop Admin Cert
- Rack Awareness
- How do I know if my hadoop hdfs filesystem has corrupt blocks, and how do I fix it?
- File Locations, Logging, and Common HDFS Commands
- Commissioning and Decommissioning Nodes in a Hadoop Cluster
- HBase
- Hive
- Elasticsearch
- Kafka
- Scylla
- Zookeeper
- Automation Tool
- Networking Devices
- Version Control
- Editor
- Systems Performance