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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”...
Ajeet Raina
3 min read

Docker 1.12 Networking Model Overview

“The Best way to orchestrate Docker is Docker” In our previous post, we talked about Swarm Mode’s built-in orchestration and distribution...
Ajeet Raina
5 min read

Docker Engine 1.12 comes with built-in Distribution & Orchestration System

Docker Engine 1.12 can be rightly called ” A Next Generation Docker Clustering & Distributed System”. Though Docker Engine 1.12 Final Release is...
Ajeet Raina
3 min read

Building Microservice applications on Docker-Datacenter (DDC) using Docker Compose

Docker-Datacenter (DDC) is targeted for both developers and IT operations team. DDC provides both developers and IT operations a common option...
Ajeet Raina
1 min read

Implementing Multi-Host Docker Networking with Docker-Datacenter (DDC)

In our previous post, we looked at detailed implementation of Docker-Datacenter-In-A-Box (Container-as-a-Service) on VMware ESXi platform. DDC pluggable architecture and open APIs allows...
Ajeet Raina
2 min read

Implementing Docker-Datacenter-In-A-Box (Container-as-a-Service) on VMware ESXi platform

The critical component for any enterprise IT, either having multiple data centers or a hybrid cloud or multiple cloud providers, is...
Ajeet Raina
4 min read

New Docker Engine 1.11 integrates runC and containerd

Docker 1.11 is two week old now. Popular for its Software Infrastructure Plumbing(SIP), Docker Inc. first focused on adoption of libnetwork,...
Ajeet Raina
4 min read

Integrating AWS and Docker Cloud 1.0 ~ A Multicloud Application Delivery Service

Docker’s acquisition of Tutum, a cross-cloud container management service has really paid-off. Two week back, Docker announced “Docker Cloud 1.0” –...
Ajeet Raina
5 min read

New Docker Engine 1.10 brings Enterprise-level security hardening – Secure Computing

Security issues like kernel exploits,  denial-of-service attacks, container breakouts, poisoned images, compromising secrets etc. has been talked a lot in recent...
Ajeet Raina
6 min read

New Docker Engine 1.10 brings Enterprise-level Security Hardening – User Namespace

User Namespace support was introduced as an experimental feature last November under Docker 1.9 version. Docker 1.10 finally brings it as...
Ajeet Raina
3 min read

Getting MariaDB Up and Running

RHEL 7 comes with MariaDB by default. Don’t get surprised if you don’t see MySQL server specific packages being displayed through...
Ajeet Raina
3 min read

Running Docker on Linux Kernel 2.6.x

Installing Docker on Linux Kernel 2.6.x is quite unstable. Docker Inc. recommends using Linux Kernel 3.x.x to have smooth Docker functionality....
Ajeet Raina
1 min read

Getting Started with Docker Swarm

Docker Swarm is 1 year old now. Docker Inc. during DockerConEU, December 2014 made the announcement of Docker Swarm. A Docker...
Ajeet Raina
4 min read

Adding new Host to Docker Swarm & Universal Control Plane through Docker Machine

In our previous post, we spent considerable time in understanding what is Universal Control Plane(UCP) and how to add hosts to...
Ajeet Raina
37 sec read

Setting up Docker Hosts on Google Compute Engine using Docker Machine

Docker Machine enables a simplified approach to set up Docker hosts on supported platforms, including Linux, Windows, OS X, and various...
Ajeet Raina
1 min read

Docker Container Management using Universal Control Plane

Docker recently announced Universal Control Plane (UCP) beta availability to the public. This tool delivers Enterprise-ready capabilities and is meant to...
Ajeet Raina
4 min read

How to reconstruct Parted Magic ISO through adding packages from Slackware

Parted Magic is a complete hard disk management solution.Parted Magic is a small live CD/USB/PXE with its elemental purpose being to...
Ajeet Raina
3 min read

Automating Hyper-V VM deployment & configuration through PowerShell

I am not Microsoft guy but recently I have been asked by my colleague to assist him in automating Hyper-V VM...
Ajeet Raina
2 min read

Building Docker-Ready Virtual Infrastructure through Docker Machine

“Is VM passe?” ~ this is an important debate ongoing around the globe among the CEOs, CFOs and CIOs. Most of...
Ajeet Raina
3 min read

New Container Network Model @ Docker 1.9

Docker 1.9 new networking is Software Defined Networking (SDN) for containers. Pushing the experimental version to the public was a right...
Ajeet Raina
10 min read

Understanding Docker Networking – Part-I

This is a tutorial series for understanding how Docker Networking really works. I have tried to put it in very simple...
Ajeet Raina
9 min read

How to build .DEB packages through Docker

Building .DEB package is still a daunting process. It involves a series of compiling, linking and building the source packages. Compiling...
Ajeet Raina
1 min read

The Anatomy of Docker Containers

You must be curious about what goes in and out of the running Docker containers. Debugging a normal Linux system processes...
Ajeet Raina
6 min read

A Docker Deployment Workflow

Docker is an amazing technology and it just simplifies both workflows and communication. Traditionally, the cycle of getting an application from...
Ajeet Raina
1 min read

Getting access to Docker Formatted Container Images on Red Hat Systems

Just like Docker, Amazon and Red Hat too announced the availability of Docker formatted container images. This is purely an effort...
Ajeet Raina
2 min read

How to get rid of Docker images with no repository?

I had dozens of Docker containers and images running on my host machine. I played around those images for my internal...
Ajeet Raina
1 min read

Run Dell SYSCFG inside a Docker Container

Docker is all about application. It doesn’t need BIOS, NIC and firmware to run any application. But its gives you flexibility...
Ajeet Raina
1 min read

Running Docker Private Registry server Frontend UI

Are you planning to setup own Docker private registry in your lab? Are you planning to bring all the in-house developers...
Ajeet Raina
1 min read

How to setup Mediawiki in seconds using Docker?

I still follow the same old traditional mediawiki software to track the roadmap, knowledge base articles, latest and updates for Linux...
Ajeet Raina
2 min read

Running Docker containers on Windows

Are you a Microsoft enthusiast? Do you want to try running containers on Windows platform? Then you have at the right...
Ajeet Raina
41 sec read

Highlights from the Dockercon 2015

Last month at San Francisco @ Dockercon15, there were numerous exciting announcement which includes runtime container called runC, Docker network, Docker...
Ajeet Raina
1 min read

How to access Docker namespace?

It is never recommended to install openssh-server on the container for just mere shell access. It is always suggested to keep your...
Ajeet Raina
1 min read

How to Link multiple Docker containers together?

Today we are going to look at an interesting concept of linking containers. In our previous post, we pulled LAMP which...
Ajeet Raina
12 min read

Setting up LAMP stack in a Docker container

Yesterday evening I decided to spend time on setting up LAMP( Linux, Apache, MySQL and PHP) stack inside a docker container....
Ajeet Raina
1 min read

How to push Docker Image to Docker Hub Registry?

This is step by step guide on how to push Docker Image to Docker Hub registry. To get started with this...
Ajeet Raina
3 min read

Automate the Bare Metal Provisioning Process through Puppet Razor

This blog post describes how to automate the bare metal provisioning of physical and virtual machines through Razor. Razor is an...
Ajeet Raina
5 min read

Getting Started with Docker – Part-II

In my previous blog post we talked about how to pull images, create containers, start and stop the containers, today we are...
Ajeet Raina
4 min read

Getting Started with Docker – Part-1

This is a step by step guide for getting started with Docker. This guide starts with a fresh CentOS 7.0 host...
Ajeet Raina
4 min read

Running Hadoop over Lustre

This blog post describes how to run Apache Hadoop over the open source distributed parallel file system like Lustre. Hadoop is...
Ajeet Raina
4 min read

Running Puppet on Solaris

Few months back I tried setting up Puppet on Solaris platform. Puppetlabs provides bits for Puppet Enterprise software for Solaris in...
Ajeet Raina
1 min read

A Dirty Guide to iPerf

By default, the Iperf client connects to the Iperf server on the TCP port 5001 and the bandwidth displayed by Iperf...
Ajeet Raina
6 min read

Setting up OpenStack Juno with 1 controller and compute node

Here is a helpful script which just setup 1 OpenStack Juno controller and 1 compute node in an easy way: File:...
Ajeet Raina
6 min read

Orchestrating Docker using Puppet

Dockers containers are revolutionizing the cloud computing world, spreading everywhere and powering developers world-wide to automate deployment of applications as a...
Ajeet Raina
4 min read

How to change Docker Image Installation Directory?

Are you running out of space while creating more and more containers? Here is a guide to change the default docker...
Ajeet Raina
2 min read

Error: /usr/bin/docker: relocation error

Are you getting the below error while starting with the fresh docker installation on CentOS 7.0? /usr/bin/docker: relocation error: /usr/bin/docker: symbol...
Ajeet Raina
22 sec read

How to find dormant users on your Linux Box?

Want to know the inactive users on your Linux machine who have not been using the machine since long time? The...
Ajeet Raina
1 min read

How to enable Docker behind the firewall?

Are you working in restricted corporate environment? Are you looking for how to run Docker behind the firewall.You can always specify...
Ajeet Raina
19 sec read

Restrict maximum simultaneous logins on Linux

Want to restrict simultaneous number of logins attempt on Linux machine? Here is the quick way of doing it. 1. Edit...
Ajeet Raina
1 min read

PowerCLI Cookbook Published !!

I am very thrilled and excited about Packtpub publisher’s recently published “PowerCLI Cookbook”. I have been part of a reveiwer team...
Ajeet Raina
19 sec read

VMware vSphere Internals Q/A

Welcome Readers !! This is a second series of VMware vSphere Q/A which is emphasized on ESXi internals and related feature...
Ajeet Raina
3 min read

Understanding Docker Container Architecture

What is Docker? Docker is a lightweight containerization technology that has gained widespread popularity in recent years. What does Docker uses?...
Ajeet Raina
2 min read

Introduction to Docker Containers

Docker is a new open source tool based on Linux container technology (LXC). LXC is an OS level virtualization method for...
Ajeet Raina
4 min read

VMware vSphere High Availability Q/A

Looking for VMware vSphere High Availability based Interview questions? I have attempted to gather important interview questions which you might find...
Ajeet Raina
15 min read

How to setup Salt Halite on CentOS 6.5

Setting up Salt Halite is not straightforward process. Its a WebUI for Salt master where you can easily run commands and...
Ajeet Raina
48 sec read

SaltStack on CentOS 6.5

SaltStack is an extremely fast and scalable systems and configuration management software for predictive orchestration, cloud and data center automation, server...
Ajeet Raina
9 min read

100 Hadoop Interview Questions

Are you preparing for Hadoop Interview? Have you spent last several hours to get the collection of Hadoop MapReduce questions? Are...
Ajeet Raina
24 min read

Learn Puppet With Me – Day 4

In today’s session, we are going to quickstart writing a basic puppet module. A Very simple example could be creating a...
Ajeet Raina
38 sec read

Learn Puppet with Me – Day 3

Puppet is an open source framework and toolset for managing the configuration of computer systems. Puppet can be used to manage...
Ajeet Raina
9 min read

How to install Nagios on Linux?

Last week I thought of setting up Nagios on my Linux Box.I installed a fresh piece of RHEL on my Virtualbox...
Ajeet Raina
6 min read

How to configure Directory Indexing in Apache?

While attending RHCE examination, I faced a lot of question related to Apache. While installation and configuration of Apache was the...
Ajeet Raina
21 sec read

Installing Open-Xchange on Ubuntu 12.04

I thought of starting my day today with Open-Xchange. I had Vmware Workstation installed on one of Windows 7 Enterprise machine....
Ajeet Raina
4 min read

Learn Puppet with Me – Day 2

Today we are going to learn about Puppet Modules. What is Puppet Modules? Puppetlabs defines it as “Modules are self-contained bundles...
Ajeet Raina
49 sec read

Learn Puppet With Me – Day 1

Today is the day 1 of Learn Puppet with Me. I am starting this thread for those who want to learn...
Ajeet Raina
52 sec read

How to setup RAID 1 on Ubuntu Linux?

RAID 1 creates a mirror on the second drive. .You will need to create RAID aware partitions on your drives before...
Ajeet Raina
2 min read

How to setup RAID 0 on Ubuntu Linux?

RAID 0 will create striping to increase read/write speeds as the data can be read and written on separate disks at...
Ajeet Raina
1 min read

How do I bind NIC interrupts to selected CPU?

I read this interesting mailing thread few weeks back. I won’t be late to share this with open source enthusiast like you....
Ajeet Raina
52 sec read

Puppet Module for JBOSS

Recently one of my colleague called me up with a problem statement where he was finding difficulty configuring JBOSS through puppet....
Ajeet Raina
3 min read

Automated shutdown of ESXi and VMs through Powershell

My friend was running a cybercafe center. He has dozens of ESXi running 100 of VMs. He was using Dell Multi-UPS...
Ajeet Raina
1 min read

Installing Java Development Toolkit (JDK) on Linux

Installing Java Development toolkit on Linux is always matter of difficulty since Oracle provides both RPM and tarballs in their official...
Ajeet Raina
2 min read

How to setup Domain Name Server (DNS) on Linux?

It has been long I was thinking of writing something about DNS(Domain Name Server). DNS is a database of the IP...
Ajeet Raina
2 min read

How to test Multicast Packet Filtering?

Today morning I started my day testing with Multicast Packet Filtering. I had buntu 12.04.1 and CentOS 6.5 in my VM...
Ajeet Raina
57 sec read

Understanding /proc/cpuinfo

A hyperthreaded processor has the same number of function units as an older, non-hyperthreaded processor. It just has two execution contexts,...
Ajeet Raina
3 min read

How to setup vsFTP server on Linux?

FTP refers to File Transfer Protocol. By default, Red Hat supports vsftp. If you do minimal RHEL installation, you mightn’t have...
Ajeet Raina
39 sec read

How to increae Swap space under Linux

“Can Linux be installed without swap space?”. This question was asked to me on one of Linux System admin interview. It...
Ajeet Raina
56 sec read

How to setup Centralized Logging System on Linux?

I was just hanging around blogs until I cam across one nice piece of setting up centralized Logging setup.I thought to...
Ajeet Raina
1 min read

How to create password-less SSH for Linux

Sometimes you might need setting up Password-less SSH for running script or for application where you dont want to use password...
Ajeet Raina
31 sec read

Installing SMARTFOX Server Pro on Debian

SmartFoxServer is a massive multiplayer platform for building games, MMO communities, virtual worlds, realtime multiplayer games. To setup SFS, in short...
Ajeet Raina
35 sec read

Setting up a Simple Samba Share – Part II

In the previous article we saw the practical implication of setting up a samba share.In this article we will explore more...
Ajeet Raina
1 min read

Setting up a Simple Samba Share – Part I

Samba is an important component to seamlessly integrate Linux/Unix Servers and Desktops into Active Directory environments using the winbind daemon.In simple...
Ajeet Raina
1 min read

Fog – An Open Source Cloning Solution

If you are a system admin who is still sticking to Clonezilla, you must probably look out to try FOG –...
Ajeet Raina
6 min read

Introduction to Puppet..

Puppet is an IT automation tool which has already gained popularity among the system admins, developers and Cloud architects. Whether its...
Ajeet Raina
10 sec read

Getting Started with Ansible

Ansible is an IT automation tool. It can configure systems, deploy software, and orchestrate more advanced IT tasks such as continuous...
Ajeet Raina
2 min read

It was an Openstack Day…OSI 2014

Yesterday I attended Open Source India 2014 event which happened in NIMHANS Convention Center, Bengaluru. If you are new to OSI,...
Ajeet Raina
3 min read

Installing Skype on CentOS 6.5

Getting skype working on CentOS 6.5 has been a daunting job for lot of system administrators. Usually I found system administrators...
Ajeet Raina
49 sec read

Automating Oracle Weblogic Server installation through shell script

Automation always saves your considerable time. Especially when you have to follow the similar step for hundreds of machine, automated scripts...
Ajeet Raina
2 min read

How to integrate Redmine with Git?

Redmine built through Ruby on Rails has been impressive free and open source web-based project management. I have been Trac quite...
Ajeet Raina
2 min read

Running Hadoop on Ubuntu 14.04 ( Multi-Node Cluster)

This is an introductory post on Hadoop for new begineers who want step by step instruction for deploying Hadoop on the...
Ajeet Raina
7 min read
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