Introduction Hadoop is a open source software use for distribute computing. It is reliable, scalable and perfectly use for big data purpose. Hadoop cluster commonly consist of NameNode, secondary NameNode, resource manager and DataNode. NameNode itself store block metadata on the file call fsimage. Secondary NameNode is a NameNode helper. It log changes to fsimage (checkpoint) but do not store the actual fsimage file. Secondary NameNode update frequently and update NameNode fsimage by combining update logs with fsimage to achieve most recent fsimage.
Most of you may heard about sensors particularly Radar, Lidar and camera. Is camera a sensors ? Yes !! Camera can be use as a sensors. Camera actually widely use on self driving car to detect an object. Camera able to identify traffic signal, driving lane and so on. Radar or radio detection and ranging is using radio signal. It’s bounce on hard surfaces but at lowest resolution. Radar is use Doppler effect by measuring changes of radar wave and compare between two reading to measure speed.
Following video show how to format hard drive on Windows 10. Steps consist of : Open search bar and type “Disk Management”. It should say “Create and format hard disk partition”. Execute. It will open new menu with all available disks. Pick disk you desire. Right click and format. “Warning” format process will erase all contain information on disk. If this is desire then continue. Format process and done. amzn_assoc_placement = "
Data structure Data structures is the specialized format to organize and manipulate data. A data structure dictate way data is acquire, and form in your computer. The goal is to use and access data on efficient manner. There are type of data structure for example array, tree, hash, and graph. Different kind of application use specific data structure to achieve efficient operation. The complexity and the use of data structure describe on big O notation where O(1) indicate a fast algorithm that will always execute in the same linear time.
Background if you have number of files need version control, you may heard about what is Git able to provide. Git is a mature version control system widely use by many peoples around the world. Storing repository online can be achieve using GitHub. There are free version for public repositories and pay version for private repositories. Other option is using Amazon AWS with local git. Amazon simple storage service (S3) is a online storage service that provide storage for your data and can be access from anywhere as long you have internet access.
Background Ability to sustain, import and export database is a necessity for database administrator to preserve smooth operations of a system. You may prefer to store database files locally and export it to production database in case you need it for quicker disaster restoration. Widely used database such as MySQL and MariaDB have similar approach in term of backup and recovery. Database dump is uncomplicated approach to deal with import and export of MySQL and MariaDB.
Introduction Cython is a software that generate a C build program for Python. What exactly is intended for ? That is most likely the question came out from everyone. Well, one good reason lots of people consider is to accelerate the speed of code process. You may also able to protect Python file by convert to .so file. However, The main objective of the Cython software is to optimize Python code, rebuild it making it operate at C speed.
Introduction Raspberry pi is popular IOT device that power up many project from hobbies project to time sensitive sensor network and automation industry. It is a small footprint device run under operating system your choice - raspbian linux or windows core IOT. However, Raspberry pi lack of hardware real time clock. Due to the fact Raspberry pi offer many advantage of small and powerful device, many developer look for a solution to synchronize device time with reference computer.
Introduction Cron is time based scheduler on Linux operating system. it run task periodically at specific time based on cron task list. There are some reason you want to execute a specific task at boot or at specific time. You may want to use #reboot cron schedule to run task at reboot. Setup Cron at Reboot To setup a cron task run when reboot for Raspberry pi, you can enter value at cron task as follow.
Introduction Domain name server (DNS) is a machine that hold information about domains and its address. It maintain IP address information of domain and can be translate to hostname. PowerDNS is a freely available high performance DNS server program runs on Linux machine. It read information from backend database and support Bind. In this tutorial we are going to process of installing PowerDNS using MariaDB as a database backend and Power admin to manage DNS server under linux ubuntu 14.