Linux

Overview There’s annoying bug on cheap Amlogic ARM-Based Single Board Computer running Armbian with Debian 11 version. I recently instaling multiple devices with single image Armbian (Debian 11). Once the process completed, all devices were unable to connect to the network due to the MAC duplicate. The originial MAC Address was gone, and instead, it generated new MAC address on each devices lead to MAC duplicatation. Because all devices were using same MAC Addresses, the network connection was rejected by the router or firewall....

Docker Offline backup docker image save -o images.tar image1 [image2 ...] This will back up the docker as .tar image. Restore Docker - Offline Load the backup docker image load -i backup.tar Rerun the image into a container docker run

Introduction MariaDB is an open-source relational database management system (RDBMS) that is a fork of MySQL. It was created by the original developers of MySQL after concerns over the acquisition of MySQL by Oracle Corporation. MariaDB replication MariaDB replication is a process that allows you to create and maintain a copy of a database on another server, which is known as a replica. Replication in MariaDB can be useful for various purposes, including load balancing, high availability, and backup....

Overview When working on remote SSH on your linux machine, you might have a situation that you need perform a long-running task such backup, patch, etc, it requires you to keep the ssh connect until the process is completed. If your session is intentionally or unintentionally disconnected, then the process will be stopped. To prevent that, you can use a utility called screen that allows to resume the sessions. What is Screren Screen is a terminal multiplexer to create multiple virtual terminal on an SSH session....

Nano File Editor Overview of nano’s shortcuts The editor’s keystrokes and their functions. File handling Keystroke Function Ctrl+S Save current file Ctrl+O Offer to write file (“Save as”) Ctrl+R Insert a file into current one Ctrl+X Close buffer, exit from nano Editing Keystroke Function Ctrl+K Cut current line into cutbuffer Alt+6 Copy current line into cutbuffer Ctrl+U Paste contents of cutbuffer Alt+T Cut until end of buffer Ctrl+] Complete current word Alt+3 Comment/uncomment line/region Alt+U Undo last action Alt+E Redo last undone action Search and replace Keystroke Function Ctrl+Q Start backward search Ctrl+W Start forward search Alt+Q Find next occurrence backward Alt+W Find next occurrence forward Alt+R Start a replacing session Deletion Keystroke Function Ctrl+H Delete character before cursor Ctrl+D Delete character under cursor Alt+Bsp Delete word to the left Ctrl+Del Delete word to the right Alt+Del Delete current line Operations Keystroke Function Ctrl+T Execute some command Ctrl+J Justify paragraph or region Alt+J Justify entire buffer Alt+B Run a syntax check Alt+F Run a formatter/fixer/arranger Alt+: Start/stop recording of macro Alt+; Replay macro Moving around...

Introduction Pi-hole and AdGuard Home are open-source network-wide ad blocker and privacy protection software designed to protect any devices on your home. It functions as a DNS (Domain Name System) sinkhole, which means it filters and blocks requests to ad and tracking domains at the DNS level before they reach the devices on your network. This effectively prevents unwanted ads, pop-ups, and tracking attempts from appearing on all your family devices....

Overview Wazuh is an open-source security information and event management (SIEM) tool. It is designed to help organizations detect and respond to security threats by providing log analysis, intrusion detection, vulnerability detection, and other security-related capabilities. Wazuh is built on top of the ELK (Elasticsearch, Logstash, and Kibana) stack and integrates with other security tools to provide a comprehensive security solution. Wazuh Components The Wazuh indexer is a highly scalable, full-text search and analytics engine....

Docker Docker is an open-source platform that automates the deployment, scaling, and management of software applications inside containers. Containers are lightweight, portable, and self-sufficient environments that encapsulate application code, runtime, system tools, libraries, and settings, enabling applications to run consistently across different computing environments, such as development laptops, on-premises servers, and cloud platforms. Docker Image A Docker image is a lightweight, standalone, isolated executable package that contains everything needed to run a piece of software or application, including the code, runtime, libraries, environment variables, and system tools....

Introduction In the event of network modifications, it is possible for nodes within your network to encounter difficulties when attempting to establish connections with hosts outside of their respective subnets. This situation often arises when the IP address of the default gateway is reassigned to a new router, while the previous device remains operational for various reasons. Hosts that had previously communicated with the old router are familiar with its MAC address and associate the old IP with that particular MAC....

Overview Rsync is a Linux command-line utility for efficiently synchronizing files and directories between two locations, either locally or over a network. It’s particularly popular for backup and mirroring purposes due to its ability to copy only the differences between source and destination files. Installation This utility is pre-installed on most linux distribution and macOS. But if you don’t have rsync installed on your system, you use the following to install....