Category Archives: Cloud computing

Smart Grid Research with the ELK Stack. You Know, For Science.

The Elasticsearch tagline is “you know, for search”. But in our case, also for science. At Servicelab, we’re using Elasticsearch, Logstash and Kibana to monitor and analyze a Smart Grid pilot. Read on for the why and how. Advertisements

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Installing a Storm cluster on CentOS hosts

Storm is a distributed, realtime computation system to reliably process unbounded streams of data. The following picture shows how data is processed in Storm: This tutorial will show you how to install Storm on a cluster of CentOS hosts. A … Continue reading

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Installing Apache Libcloud on CentOS

Apache Libcloud is a standard Python library that abstracts away differences among multiple cloud provider APIs. At the moment it can be used to manage four different kinds of cloud services: servers, storage, loadbalancers and DNS. Here are the steps … Continue reading

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Changing CPU and memory settings on XenServer VMs

You can change the CPU and memory settings of XenServer virtual machines using the API. XenServer allows you to set the priority of the virtual machine CPU (called weight), set a limit on the amount of CPU the virtual machine … Continue reading

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Getting CPU, memory, disk and network metrics from XenServer

In a previous article we looked at getting CPU and memory metrics from XenServer. As noted in that article, as of version 5.5 of XenServer, the preferred way of getting virtual machine metrics is through HTTP calls to get RRD … Continue reading

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Getting XenServer VM metrics in Java

XenServer is a product of Citrix that can run virtual machines on a set of physical hosts called a pool. There is an API that allows you to create programs that interact with the XenServer pool. There are some function … Continue reading

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