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Virtualization and Cloud

Jonathan Gershater

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Top Stories by Jonathan Gershater

Infrastructure as a Service is one of the three delivery methods of cloud computing (the other two are Platform as a Service and Software as a Service). Users of IaaS have the expertise to maintain operating systems and applications, but don't wish to purchase server, storage and networking hardware and a datacenter to house the hardware. The cloud provider provides these services from a shared pool. The cloud user will then use the virtual machines to fulfill their computing requirements and may install their own operating system and will install their own applications on the virtual machines. Some characteristics of IaaS: Elasticity: you can provision (add) or de-provision (remove) cloud instances to scale up or down your environment. Firewalls: may be host-based on each cloud instance (virtual machine - see below) and/or an Internet firewall that offers the c... (more)

High Availability, Fault Tolerance and Disaster Recovery in AWS

Amazon Web Services – Disaster Recovery, High Availability and Fault Tolerance Abbreviations used: AWS - Amazon Web Services AMI - Amazon Machine Instance DR - Disaster Recovery FT - Fault Tolerance HA - High Availability Non-technical introduction. High Availability and Fault Tolerance – the requirement that a computer application be seemlessly available to users without interruption, literally “no (or very little) fault will be tolerated”. In simple speak, this means that I am able to use a computer application even though in the background there may be outages, for example har... (more)

Examining Excellent Eucalyptus

Eucalyptus is an open source Infrastructure as a Service cloud offering. What is unique about Eucalyptus is that it is compatible with Amazon AWS APIs. This means that you can: Use Eucalyptus commands to manage Amazon or Eucalyptus instances. Freely move instances between a Eucalyptus private cloud and the Amazon Public cloud to create a hybrid cloud. Eucalyptus leverages operating system virtualization, such as KVM or XEN, to achieve isolation between applications and stacks. Operating system virtualization dedicates CPU and RAM to systems and applications such that they don't ... (more)

Hadoop Deep Dive: HDFS and MapReduce

Following my initial introduction to Hadoop and overview of Hadoop components, I studied the Yahoo Hadoop tutorial,  and have a deeper understanding of Hadoop. I  would like to share my learning and help others understand Hadoop. Why does Hadoop require HDFS, what's wrong with NFS? Normal 0 false false false EN-US JA X-NONE Nothing! NFS been around for years and is incredibly stable. A distributed file system, such as NFS, provides the functionality required for servers to share files. It does this by exposing a volume to the network, which users connect to over the TCP/IP proto... (more)

Cloud Computing Easily Understood - PaaS

In a previous post, I described Infrastructure as a Service (IaaS). In essence, if I use the service of an Infrastructure provider, who provides hardware: servers, networking, storage and firewalls, it is then incumbent upon me to install and maintain my own applications. However, I don't incur the capital and operating costs of maintaing the hardware and datacenters. To install and maintain web applications in an IaaS model, I typically need to: Install databases, web servers and application servers onto the (virtual) servers provided by the IaaS provider Write or purchase an ap... (more)