80 lines
3.6 KiB
XML
80 lines
3.6 KiB
XML
<?xml version="1.0" encoding="UTF-8"?>
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<chapter xmlns="http://docbook.org/ns/docbook"
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xmlns:xi="http://www.w3.org/2001/XInclude"
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xmlns:xlink="http://www.w3.org/1999/xlink"
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version="5.0"
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xml:id="massively_scalable">
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<title>Massively scalable</title>
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<para>A massively scalable architecture is a cloud
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implementation that is either a very large deployment, such as
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a commercial service provider might build, or
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one that has the capability to support user requests for large
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amounts of cloud resources. An example is an
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infrastructure in which requests to service 500 or more instances
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at a time is common. A massively scalable infrastructure
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fulfills such a request without exhausting the available
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cloud infrastructure resources. While the high capital cost
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of implementing such a cloud architecture means that it is
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currently in limited use, many organizations are planning
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for massive scalability in the future.</para>
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<para>A massively scalable OpenStack cloud design presents a
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unique set of challenges and considerations. For the most part
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it is similar to a general purpose cloud architecture, as it
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is built to address a non-specific range of potential use
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cases or functions. Typically, it is rare that particular
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workloads determine the design or configuration of massively
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scalable clouds. Like the general purpose cloud, the massively
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scalable cloud is most often built as a platform for a variety
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of workloads. Because private organizations rarely require
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or have the resources for them, massively scalable OpenStack clouds
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are generally built as commercial, public cloud offerings.</para>
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<para>Services provided by a massively scalable OpenStack cloud
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include:</para>
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<itemizedlist>
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<listitem>
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<para>Virtual-machine disk image library</para>
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</listitem>
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<listitem>
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<para>Raw block storage</para>
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</listitem>
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<listitem>
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<para>File or object storage</para>
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</listitem>
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<listitem>
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<para>Firewall functionality</para>
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</listitem>
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<listitem>
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<para>Load balancing functionality</para>
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</listitem>
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<listitem>
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<para>Private (non-routable) and public (floating) IP
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addresses</para>
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</listitem>
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<listitem>
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<para>Virtualized network topologies</para>
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</listitem>
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<listitem>
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<para>Software bundles</para>
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</listitem>
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<listitem>
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<para>Virtual compute resources</para>
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</listitem>
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</itemizedlist>
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<para>Like a general purpose cloud, the instances deployed in a
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massively scalable OpenStack cloud do not necessarily use
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any specific aspect of the cloud offering (compute, network,
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or storage). As the cloud grows in scale, the number of
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workloads can cause stress on all the cloud
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components. This adds further stresses to supporting
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infrastructure such as databases and message brokers. The
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architecture design for such a cloud must account for these
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performance pressures without negatively impacting user
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experience.</para>
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<xi:include href="massively_scalable/section_user_requirements_massively_scalable.xml"/>
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<xi:include href="massively_scalable/section_tech_considerations_massively_scalable.xml"/>
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<xi:include href="massively_scalable/section_operational_considerations_massively_scalable.xml"/>
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</chapter>
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