manish
Querying elasticsearch with REST json
You may like to read ELK installation and configuration and ELK with syslog and SNMP before this. Recently I was looking to build some useful queries to search elasticsearch database having syslog messages from my syslog-ng servers. My requirement was to pull records within datetime ranges matching with set of hosts/IPs and text patterns within […]
Create a simple CA to sign SSL certificates
Securing traffic on various apps in organizations or even in a small home lab is very important to protect passwords and other critical information floating on LAN or WiFi. Let us build a handy CA in simple steps to generate own certificates which can be used in internal applications. Before this you may also like […]
IoT enabled Smart doorbell
How useful would it be if you are notified on phone with the photo of visitor on door moment doorbell rings 🙂 Let us build a low cost and simple solution without intercepting anything on 220v supply of doorbell. Things you need 1) NodeMCU board. 2) sound sensor with digital output(it a simple mic hooked […]
Reliable machine to machine communication using MQTT QoS
MQTT messaging provides three levels of quality of service. Depending upon the requirement QoS levels can be selected for various services. QoS level 0 This is the default QoS level when QoS is not explicitly set. This is simplest form of MQTT message where client publishes the message to broker and there is no acknowledgment […]
IoT ready relay to operate 220v AC home appliances
When I am away from home during long vacations I felt need of having control of some lights back at home, specially during Diwali holidays to turn on lights at night. I had already interfaced my 4 channel relay with raspberry and NodeMCU and control it via ssh terminal on raspberry and serial port of […]
How to operate relay using NodeMCU
NodeMCU board is powered by ESP8266 WiFi unit which gives advantage of controlling circuits connected to NodeMCU over home WiFi or even internet. Idea of connecting relay with NodeMCU will enable us to control 220AC appliances at home from anywhere in the world over internet. Some basics first: 1) NodeMCU does provides 3.3V power and […]
Build own IoT enabled weather station
After performing some stand alone tests with my DHT22 weather sensor on NodeMCU board and MQTT broker on raspberry, I thought to publish weather data on my home MQTT network. To do this I took part of code in examples of Adafruit sensor and MQTT libraries. To start you will need following three libraries installed […]
MQTT protocol – Telemetry for IoT
Message Queuing Telemetry Transport (MQTT) is a light weight message exchange protocol. This protocol has emerged as efficient way of telemetry data transmission/reception for IoT devices. Common programming languages have MQTT libraries available to implement this protocol. Apart from IoT you can think of using MQTT in other areas as well. For eg facebook uses […]
Connecting 220V AC load to relay controlled by raspberry pi GPIO
Read http://www.mka.in/wp/raspberry-pi-3b-with-5v-4-channel-relay/ first. After gaining confidence in simple relay control using raspberry pi GPIO pins I have now tried connecting 220V AC load to the relay controlled by raspberry. For sake of safety I bought a pair of male-female plug and socket to connect AC load. Connection is really simple. 1) Connect one terminal of […]
Raspberry pi 3B with 5V 4 channel relay
I have been using raspberry pi boards since long. So far I have used these for applications such as media center, home cloud, pi-hole and some of my own written apps. This time I thought to extend scope to control external electrical devices. To start with I have purchased a 5V 4 channel relay and […]