Arvind Singh arvind-india

Docker - How to cleanup (unused) resources

Once in a while, you may need to cleanup resources (containers, volumes, images, networks) ...

delete volumes

// see: https://github.com/chadoe/docker-cleanup-volumes

$ docker volume rm $(docker volume ls -qf dangling=true)

$ docker volume ls -qf dangling=true | xargs -r docker volume rm

For this example, I have a very simple Node.js applications that increments a counter stored on Redis. I want to run Redis and the node application independently as I want to have the ability to scale the node application depending on the load. To start off, I have 3 instances of the node server running the application. I have an Nginx server in front of node for load balancing the node instances.

Let’s now talk in terms of containers, specifically Docker containers. Simple; 1 container for each service/process!

1 Redis container
3 Node containers
1 Nginx container So, the overall picture looks something like this:

	#!/bin/bash

	# remove exited containers:
	docker ps --filter status=dead --filter status=exited -aq \| xargs -r docker rm -v

	# remove unused images:
	docker images --no-trunc \| grep '<none>' \| awk '{ print $3 }' \| xargs -r docker rmi

	# remove unused volumes:
	find '/var/lib/docker/volumes/' -mindepth 1 -maxdepth 1 -type d \| grep -vFf <(

	#!/usr/bin/env python
	# read CC2650 SensorTag by JP Mens
	# follow https://smidgeonpigeon.wordpress.com/2015/07/21/raspberry-pi-2-ble-ti-sensor-tag/
	# to get started, but use Sensortag2650.py

	import time
	import json
	import struct
	import Sensortag2650 as sensortag
	import paho.mqtt.publish as mqtt

	// This function node combines all of the async values
	// reported by the sensor tag node into a single
	// payload. The flow will only continue when all values
	// have been received.

	var payload = context.get('payload') \|\| { data: {} };

	// Number of total attributes to report.
	// When we collect all attributes from the
	// sensor tag, the flow will continue.