Turn Your Raspberry Pi into Out-of-band Monitoring Device using Docker

Why should I deploy Docker to IoT devices? What are the use cases of running containers inside the IoT device like Raspberry Pi? Is Docker on IoT devices just for hobbyists? – To answer all these burning queries, I just thought of sharing one of the most interesting use case inside the datacentre lab which will surely attract infinite number of possibilities and implementation with Docker containers. Imagine a small credit card size server sitting just below your ToR (Top of the Rack) switch, consuming very low power ( similar to your mobile device), not bound by wired Ethernet( Wi-Fi...

Docker 1.12.1 Swarm Mode & Persistent Storage with DellEMC RexRay on AWS Platform

“Does Docker Engine 1.12 has storage discovery similar to Service Discovery and Orchestration Feature? What is the Volume/Persistent Storage story in 1.12 Swarm Mode? Which will be the best solution for my DB persistence? ” – are few common questions which I faced in almost every online meetup, blogs and Docker webinar. Docker 1.12 release was totally focused on Orchestration feature but there has been subtle changes in regards to volumes, volume drivers and storage. Under this blog post, I will be answering the following queries: What’s new in Docker 1.12 Persistent Storage? How does Persistent storage work in case...

Building the first CentOS 7.2 ARM docker image on Raspberry Pi 3

In the previous post, I showed how to get Docker 1.12.1 up and running on Raspberry Pi3 in just 5 minutes. Under 1.12.1 release, Docker Inc. provided a FIRST ARM debian package which can be installed using a single curl command. It works great and there has been numerous Ubuntu, Alpine and Debian based ARM Docker images been built and pushed out to Dockerhub. If you are CentOS/Red Hat user, you might be interested in building CentOS based ARM images on top of Raspberry Pi. As of today, there is NO CentOS based Docker image available for ARM architecture under...

What’s new in Docker 1.12 Scheduling? – Part-I

In our previous posts, we spent considerable amount of time deep-diving into Swarm Mode which is in-built orchestration engine in Docker 1.12 release. The Swarm Mode orchestration engine comprises of desired state reconciliation, replicated and global services, configuration updates in the form of parallelism/delay and restart policies to name a few. Docker Engine 1.12 is not just about the multi-host and multi-container orchestration but there are numerous improvements in terms of Scheduling, Cluster management and Security. Under this post, I am going to talk about scheduling(primarily Engine & Swarm Labels) aspect in terms of new service API introduced under 1.12...

Docker 1.12.1 on Raspberry Pi 3 in 5 minutes

Docker 1.12.1 Final Release got announced last Friday. This update release holds solid number of bug fixes and feature improvements targeted to make Swarm Mode orchestration more stable and consistent. There has been critical bug fixes around node management, service discovery,  ingress load-balancing and much more. But the BIG news comes for “Raspberry Pi” enthusiasts. With 1.12.1, a FIRST ARM debian package has been officially made available.In case you are wondering what it actually means? – If you have Raspberry Pi box and microSD card loaded with Raspbian OS inserted into Pi box, all you need is to power-on your...

What’s new in Docker 1.12.0 Load-Balancing feature?

In the previous blog post, we deep-dived into Service Discovery aspects of Docker. A service is now a first class citizen in Docker 1.12.0 which allows replication, update of images and dynamic load-balancing. With Docker 1.12, services can be exposed on ports on all Swarm nodes and load balanced internally by Docker using either a virtual IP(VIP) based or DNS round robin(RR) based Load-Balancing method or both. In case you are very new to Load-balancing concept, the load balancer assigns workload to a set of networked computer servers or components in such a manner that the computing resources are used in...

Demonstrating Docker 1.12 Service Discovery with Docker Compose

Docker 1.12 is GA now. Thanks to Docker Inc. core Team and community support for releasing it on time as promised during DockerCon 2016.In my earlier post, I briefed around Service Discovery concept and how does it work in terms of  Swarm Mode. As we are well aware, Swarm Mode is an optional mode which can be ON and OFF based on your choice and requirement. Under this blog post, I am going to demonstrate service discovery while playing around with docker-compose. I have a Ubuntu 16.04 machine upgraded with Docker 1.12 GA version. I have docker-compose 1.8.0 running on the...

Demystifying Service Discovery under Docker Engine 1.12.0

Prior to Docker 1.12 release, setting up Swarm cluster needed some sort of service discovery backend. There are multiple discovery backends available like hosted discovery service, using a static file describing the cluster, etcd, consul, zookeeper or using static list of IP address. Thanks to Docker 1.12 Swarm Mode, we don’t have to depend upon these external tools and complex configurations. Docker Engine 1.12 runs it’s own internal DNS service to route services by name.Swarm manager nodes assign each service in the swarm a unique DNS name and load balances running containers. You can query every container running in the swarm through...

Understanding Node Failure Handling under Docker 1.12 Swarm Mode

In the last Meetup (#Docker Bangalore), there has been lots of curiosity around “Desired State Reconciliation” & “Node Management” feature in case of Docker Engine 1.12 Swarm Mode.  I found lots of queries post the presentation session on how Node Failure Handling is taken care in case of new Docker Swarm Mode , particularly when master node participating in the raft consensus goes down. Under this blog post, I will demonstrate how Master Node Failure is achieved which is very specific to RAFT consensus algorithm. We will look at how Swarmkit (the technical foundation of Swarm Mode implementation) uses the raft consensus algorithm...

Docker 1.12 Swarm Mode – Under the hood

Today Docker Inc. released Engine 1.12 Release Candidate 4 with numerous improvements and added security features. With an optional “Swarm Mode” feature rightly integrated into core Docker Engine, a native management of a cluster of Docker Engines, orchestration, decentralized design, service and application deployment, scaling, desired state reconciliation, multi-host networking, service discovery and routing mesh implementation is just a matter of few liner commands. In the previous posts, we introduced Swarm Mode, implemented a simple service applications and went through 1.12 networking model. Under this post, we will deep dive into Swarm Mode and study what kind of communication gets generated...