(i) Workloads of server changes dynamically. Sometimes user request is low and some cases user demand is very high (for example during the end of the month). It is practically not possible to provision additional servers manually. So, Virtual Machine Migration accommodates for the changing workloads automatically (It can adapt to both additional workloads and reduced workloads). (ii) A scheduled maintenance normally results in some downtime for the users of the server. But with Virtual Machine Migration, the VM can be migrated to some other server (for that period of scheduled maintenance) and brought back to the host server after the maintenance is completed. Virtual Machine Migration can also migrate Virtual Machines in case of unscheduled server downtime (due to some fault in server), so that user’s experience high availability of applications at all times (Rajesh, K. (2014) AU30: The in-text citation "Rajesh, K. (2014)" is not in the reference list. Please correct the citation, add the reference to the list, or delete the citation. . (iii) Virtual Machine Migration can also be used for Disaster Recovery (DR). This process involves setting up of similar resources in a DR site with high speed WAN links and specialized network connectivity equipment. The Virtual Machines and their memory states are frequently synchronized (replicated) between the primary servers and the servers in the DR site, so that migration can happen quickly in case of a disaster. (iv) It’s easier to migrate a Virtual Machine from one server to another, than migrating the operating system and application(s) individually without disrupting the services.
Published in Chapter:
An Evolutionary Approach for Load Balancing in Cloud Computing
Subashis Mohapatra (National Institute of Technology – Rourkela, India) and Banshidhar Majhi (National Institute of Technology – Rourkela, India)
Copyright: © 2015
|Pages: 31
DOI: 10.4018/978-1-4666-6559-0.ch020
Abstract
Cloud computing has many issues related to privacy, security, scalability, elasticity, and efficiency. Load balancing is one of the vexing issues in cloud computing. Load balancing ensures that all processors in the system have approximately an equal amount of work at any instance of time. In this chapter, the authors analyze some load-balancing algorithms and compare their performances using cloud analyst. Lots of references are added for the benefit of readers.