openstack/openstack-manuals
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Merge "Arch Design: Add glossentries, use common glossary"

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4
doc/arch-design/bk-openstack-arch-design.xml
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@@ -69,7 +69,7 @@
<xi:include href="ch_hybrid.xml"/>
<xi:include href="ch_massively_scalable.xml"/>
<xi:include href="ch_specialized.xml"/>
<xi:include href="ch_references.xml"/><!--
<xi:include href="ch_glossary.xml"/>-->
<xi:include href="ch_references.xml"/>
<xi:include href="../common/app_support.xml"/>
<glossary role="auto"/>
</book>

146
doc/arch-design/ch_glossary.xml
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@@ -5,74 +5,36 @@
version="5.0"
xml:id="arch-design-glossary">
<title>Glossary</title>
<!--
This file needs to be removed. For the remaining entries,
figure out which ones should go to the common glossary in
../glossary/glossary-terms.xml and which ones can be removed
completely. For each entry that should appear in the Arch
Design Glossary, a glossterm markup needs to be done in the
text.
-->
<itemizedlist>
<listitem>
<para>6to4 - A mechanism that allows IPv6 packets to be
transmitted over an IPv4 network, providing a strategy
for migrating to IPv6.</para>
</listitem>
<listitem>
<para>AAA - authentication, authorization and
auditing.</para>
</listitem>
<listitem>
<para>Anycast - A network routing methodology that routes
traffic from a single sender to the nearest node, in a
pool of nodes.</para>
</listitem>
<listitem>
<para>ARP - Address Resolution Protocol - the protocol by
which layer 3 IP addresses are resolved into layer 2,
link local addresses.</para>
</listitem>
<listitem>
<para>BGP - Border Gateway Protocol is a dynamic routing
protocol that connects autonomous systems together.
Considered the backbone of the Internet, this protocol
connects disparate networks together to form a larger
network.</para>
</listitem>
<listitem>
<para>Boot Storm - When hundreds of users log in to and
consume resources at the same time, causing
significant performance degradation. This problem is
particularly common in Virtual Desktop Infrastructure
(VDI) environments.</para>
traffic from a single sender to the nearest node, in a
pool of nodes.</para>
</listitem>
<listitem>
<para>Broadcast Domain - The layer 2 segment shared by a
group of network connected nodes.</para>
</listitem>
<listitem>
<para>Bursting - The practice of utilizing a secondary
environment to elastically build instances on-demand
when the primary environment is resource
constrained.</para>
</listitem>
<listitem>
<para>Capital Expenditure (CapEx) - A capital expense,
capital expenditure, CapEx is an initial cost for
building a product, business, or system.</para>
</listitem>
<listitem>
<para>Cascading Failure - A scenario where a single
failure in a system creates a cascading effect, where
other systems fail as load is transferred from the
failing system.</para>
</listitem>
<listitem>
<para>CDN - Content delivery network - a specialized
network that is used to distribute content to clients,
typically located close to the client for increased
performance.</para>
</listitem>
<listitem>
<para>Cells - An OpenStack Compute (Nova) feature, where a
compute deployment can be split into smaller clusters
or cells with their own queue and database for
performance and scalability, while still providing a
single API endpoint.</para>
</listitem>
<listitem>
<para>CI/CD - Continuous Integration / Continuous
Deployment, a methodology where software is
@@ -113,23 +75,6 @@
<para>Direct Attached Storage (DAS) - Data storage that is
directly connected to a machine.</para>
</listitem>
<listitem>
<para>DefCore - DefCore sets base requirements by defining
capabilities, code and must-pass tests for all
OpenStack products. This definition uses community
resources and involvement to drive interoperability by
creating the minimum standards for products labeled
"OpenStack." See
<link xlink:href="https://wiki.openstack.org/wiki/Governance/CoreDefinition">https://wiki.openstack.org/wiki/Governance/CoreDefinition</link>
for more information.</para>
</listitem>
<listitem>
<para>Desktop as a Service (DaaS) - A platform that
provides a suite of desktop environments that users
may log in to receive a desktop experience from any
location. This may provide general use, development,
or even homogenous testing environments.</para>
</listitem>
<listitem>
<para>Direct Server Return - A technique in load balancing
where an initial request is routed through a load
@@ -166,12 +111,6 @@
reassigned to running instances on the fly. The
OpenStack equivalent is a Floating IP.</para>
</listitem>
<listitem>
<para>Encapsulation - The practice of placing one packet
type within another for the purposes of abstracting or
securing data. Examples include GRE, MPLS, or
IPSEC.</para>
</listitem>
<listitem>
<para>External Cloud - A cloud environment that exists
outside of the control of an organization. Referred to
@@ -213,13 +152,6 @@
machines, providing very high aggregate bandwidth
across the cluster.</para>
</listitem>
<listitem>
<para>High Availability (HA) - High availability system
design approach and associated service implementation
that ensures a prearranged level of operational
performance will be met during a contractual
measurement period.</para>
</listitem>
<listitem>
<para>High Performance Computing (HPC) - Also known as
distributed computing - used for computation intensive
@@ -238,15 +170,6 @@
gateway, and has been described in detail in RFC
2281.</para>
</listitem>
<listitem>
<para>Hybrid Cloud - Hybrid cloud is a composition of two
or more clouds (private, community or public) that
remain distinct entities but are bound together,
offering the benefits of multiple deployment models.
Hybrid cloud can also mean the ability to connect
colocation, managed and/or dedicated services with
cloud resources.</para>
</listitem>
<listitem>
<para>Interior Border Gateway Protocol (iBGP) - Interior
Border Gateway Protocol is an interior gateway
@@ -262,12 +185,6 @@
This routing information can then be used to route
network-level protocols like IP.</para>
</listitem>
<listitem>
<para>Input/Output Operations Per Second (IOPS) - A common
performance measurement used to benchmark computer
storage devices like hard disk drives, solid state
drives, and storage area networks.</para>
</listitem>
<listitem>
<para>jClouds - An open source multi-cloud toolkit for the
Java platform that gives you the freedom to create
@@ -285,14 +202,6 @@
<para>Jumbo Frame - Ethernet frames with more than 1500
bytes of payload.</para>
</listitem>
<listitem>
<para>Kernel-based Virtual Machine (KVM) - A full
virtualization solution for Linux on x86 hardware
containing virtualization extensions (Intel VT or
AMD-V). It consists of a loadable kernel module, that
provides the core virtualization infrastructure and a
processor specific module.</para>
</listitem>
<listitem>
<para>LAG - Link aggregation group is a term to describe
various methods of combining (aggregating) multiple
@@ -301,18 +210,6 @@
could sustain, and to provide redundancy in case one
of the links fail.</para>
</listitem>
<listitem>
<para>Layer 2 - The data link layer provides a reliable
link between two directly connected nodes, by
detecting and possibly correcting errors that may
occur in the physical layer.</para>
</listitem>
<listitem>
<para>Layer 3 - The network layer provides the functional
and procedural means of transferring variable length
data sequences (called datagrams) from one node to
another connected to the same network.</para>
</listitem>
<listitem>
<para>Legacy System - An old method, technology, computer
system, or application program that is considered
@@ -370,15 +267,6 @@
modeled in means other than the tabular relations used
in relational databases.</para>
</listitem>
<listitem>
<para>Open vSwitch - Open vSwitch is a production quality,
multilayer virtual switch licensed under the open
source Apache 2.0 license. It is designed to enable
massive network automation through programmatic
extension, while still supporting standard management
interfaces and protocols (for example NetFlow, sFlow, SPAN,
RSPAN, CLI, LACP, 802.1ag).</para>
</listitem>
<listitem>
<para>Operational Expenditure (OPEX) - An operating
expense, operating expenditure, operational expense,
@@ -405,12 +293,6 @@
overwhelmed by continuous multicast or broadcast
traffic.</para>
</listitem>
<listitem>
<para>Platform-as-a-Service (PaaS) - Platform-as-a-Service
is a category of cloud computing services that
provides a computing platform and a solution stack as
a service.</para>
</listitem>
<listitem>
<para>Power Usage Effectiveness (PUE) - Power usage
effectiveness is a measure of how efficiently a
@@ -570,11 +452,5 @@
network that covers a broad area using leased or
private telecommunication lines.</para>
</listitem>
<listitem>
<para>Xen - Xen is a hypervisor using a microkernel
design, providing services that allow multiple
computer operating systems to execute on the same
computer hardware concurrently.</para>
</listitem>
</itemizedlist>
</chapter>

6
doc/arch-design/ch_hybrid.xml
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@@ -6,14 +6,16 @@
xml:id="hybrid">
<title>Hybrid</title>
<para>Hybrid cloud, by definition, means that the design spans
<para><glossterm baseform="hybrid cloud">Hybrid cloud</glossterm>,
by definition, means that the design spans
more than one cloud. An example of this kind of architecture
may include a situation in which the design involves more than
one OpenStack cloud (for example, an OpenStack-based private
cloud and an OpenStack-based public cloud), or it may be a
situation incorporating an OpenStack cloud and a non-OpenStack
cloud (for example, an OpenStack-based private cloud that
interacts with Amazon Web Services). Bursting into an external
interacts with Amazon Web Services).
<glossterm baseform="bursting">Bursting</glossterm> into an external
cloud is the practice of creating new instances to alleviate
extra load where there is no available capacity in the private
cloud.</para>

2
doc/arch-design/ch_specialized.xml
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@@ -38,7 +38,7 @@
<listitem>
<para>
<link
linkend="desktop-as-a-service">Desktop-as-a-Service</link>:
linkend="desktop-as-a-service"><glossterm>Desktop-as-a-Service</glossterm></link>:
This is for organizations that want to run a virtualized
desktop environment on a cloud. This can apply to
private or public clouds.

10
doc/arch-design/compute_focus/section_architecture_compute_focus.xml
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@@ -455,10 +455,12 @@
<para>OpenStack Networking provides a wide variety of networking services
for instances. There are many additional networking software packages
that might be useful to manage the OpenStack components themselves.
Some examples include software to provide load balancing, network
redundancy protocols, and routing daemons. Some of these software
packages are described in more detail in the OpenStack HA Guide (refer
to Chapter 8 of the OpenStack High Availability Guide).</para>
Some examples include software to provide load balancing,
network redundancy protocols, and routing daemons. Some of these
software packages are described in more detail in the
<citetitle>OpenStack High Availability Guide</citetitle> (<link
xlink:href="http://docs.openstack.org/high-availability-guide/content">http://docs.openstack.org/high-availability-guide/content</link>).
</para>
<para>For a compute-focused OpenStack cloud, the OpenStack infrastructure
components will need to be highly available. If the design does not
include hardware load balancing, networking software packages like

3
doc/arch-design/compute_focus/section_prescriptive_examples_compute_focus.xml
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@@ -51,7 +51,8 @@
doubling compute capacity through the addition of an
additional data center in 2013 while maintaining the same
levels of compute staff.</para>
<para>The CERN solution uses Cells for segregation of compute
<para>The CERN solution uses <glossterm baseform="cell">cells</glossterm>
for segregation of compute
resources and to transparently scale between different data
centers. This decision meant trading off support for security
groups and live migration. In addition some details like

8
doc/arch-design/generalpurpose/section_architecture_general_purpose.xml
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@@ -38,8 +38,8 @@
for a general purpose OpenStack architecture design must
provide an equal or nearly equal balance of compute capacity
(RAM and CPU), network capacity (number and speed of links),
and storage capacity (gigabytes or terabytes as well as I-O
Operations Per Second (IOPS).</para>
and storage capacity (gigabytes or terabytes as well as Input/Output
Operations Per Second (<glossterm>IOPS</glossterm>).</para>
<para>Server hardware is evaluated around four conflicting
dimensions:
</para>
@@ -639,7 +639,9 @@
<para>Selecting a commercially supported hypervisor,
such as Microsoft Hyper-V, will result in a different
cost model rather than community-supported open source
hypervisors including KVM, Kinstance or Xen. When
hypervisors including <glossterm
baseform="kernel-based VM (KVM)">KVM</glossterm>,
Kinstance or <glossterm>Xen</glossterm>. When
comparing open source OS solutions, choosing Ubuntu
over Red Hat (or vice versa) will have an impact on
cost due to support contracts. On the other hand,

3
doc/arch-design/generalpurpose/section_operational_considerations_general_purpose.xml
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@@ -19,7 +19,8 @@
with penalties for not meeting the contractual obligations.
The strictness of the SLA dictates the level of redundancy and
resiliency in the OpenStack cloud design. Knowing when and
where to implement redundancy and HA is directly affected by
where to implement redundancy and high availability is
directly affected by
expectations set by the terms of the SLA. Some of the SLA
terms that will affect the design include:</para>
<itemizedlist>

2
doc/arch-design/generalpurpose/section_tech_considerations_general_purpose.xml
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@@ -641,7 +641,7 @@
storage or OpenStack Block storage to provide a level of
guarantee to match service features.</para>
<para>
For more information on HA in OpenStack, see the <link
For more information on high availability in OpenStack, see the <link
xlink:href="http://docs.openstack.org/high-availability-guide"><citetitle>OpenStack
High Availability Guide</citetitle></link>.
</para>

6
doc/arch-design/hybrid/section_architecture_hybrid.xml
View File

@@ -92,7 +92,8 @@
(heat).</para>
</listitem>
<listitem>
<para>Deploy a Platform-as-a-Service (PaaS) technology
<para>Deploy a <glossterm>Platform-as-a-Service (PaaS)</glossterm>
technology
such as Cloud Foundry or OpenShift that abstracts the
upper-layer services from the underlying cloud
platform. The unit of application deployment and
@@ -120,7 +121,8 @@
multiple cloud architectures. It could be an important factor
to assess when choosing a CMP and cloud provider.
Considerations are: functionality, security, scalability and
high availability (HA). Verification and ongoing testing of
<glossterm>high availability (HA)</glossterm>.
Verification and ongoing testing of
the critical features of the cloud endpoint used by the
architecture are important tasks.</para>
<itemizedlist>

12
doc/arch-design/introduction/section_how_this_book_is_organized.xml
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@@ -45,8 +45,8 @@
<para>
<link linkend="network_focus">Network focused</link>: A
cloud depending on high performance and reliable
networking, such as a content delivery network
(CDN).
networking, such as a <glossterm
>content delivery network (CDN)</glossterm>.
</para>
</listitem>
<listitem>
@@ -111,8 +111,8 @@
deployed.</para>
</listitem>
</itemizedlist>
<!--
<para>A glossary covers the terms used in the
book.</para>
-->
<para>
A glossary covers the terms used in the book.
</para>
</section>

3
doc/arch-design/massively_scalable/section_tech_considerations_massively_scalable.xml
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@@ -62,7 +62,8 @@
entire racks or even groups of racks at a time with each new
addition of nodes exposed via one of the segregation concepts
mentioned herein.</para>
<para>Cells provide the ability to subdivide the compute portion
<para><glossterm baseform="cell">Cells</glossterm> provide the ability
to subdivide the compute portion
of an OpenStack installation, including regions, while still
exposing a single endpoint. In each region an API cell is
created along with a number of compute cells where the

11
doc/arch-design/network_focus/section_architecture_network_focus.xml
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@@ -54,7 +54,9 @@
solutions for traffic shaping or other network functions will
be needed.</para>
<para>Depending on the selected design, Neutron itself may not
even support the required layer 3 network functionality. If it
even support the required
<glossterm baseform="Layer-3 network">layer 3 network</glossterm>
functionality. If it
is necessary or advantageous to use the provider networking
mode of Neutron without running the layer 3 agent, then an
external router will be required to provide layer 3
@@ -118,7 +120,9 @@
Protocol (HSRP). There are also the considerations of whether
to deploy Neutron or Nova-network and which plug-in to select
for Neutron. If using an external system, Neutron will need to
be configured to run layer 2 with a provider network
be configured to run
<glossterm baseform="Layer-2 network">layer 2</glossterm>
with a provider network
configuration. For example, it may be necessary to implement
HSRP to terminate layer 3 connectivity.</para>
<para>Depending on the workload, overlay networks may or may not
@@ -148,7 +152,8 @@
progress to support stateless and stateful dhcpv6 as well as
IPv6 floating IPs without NAT. Some workloads become possible
through the use of IPv6 and IPv6 to IPv4 reverse transition
mechanisms such as NAT64 and DNS64 or 6to4, because these
mechanisms such as NAT64 and DNS64 or <glossterm>6to4</glossterm>,
because these
options are available. This will alter the requirements for
any address plan as single-stacked and transitional IPv6
deployments can alleviate the need for IPv4 addresses.</para>

20
doc/arch-design/network_focus/section_tech_considerations_network_focus.xml
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@@ -118,8 +118,10 @@
without IP addresses and ICMP.</para>
</listitem>
<listitem>
<para>Configuring ARP is considered complicated on large
layer 2 networks.</para>
<para>
Configuring <glossterm
baseform="Address Resolution Protocol (ARP)">ARP</glossterm>
is considered complicated on large layer 2 networks.</para>
</listitem>
<listitem>
<para>All network devices need to be aware of all MACs,
@@ -172,9 +174,10 @@
straightforward.</para>
</listitem>
<listitem>
<para>Layer 3 can be configured to use BGP confederation
for scalability so core routers have state
proportional to number of racks, not to the number of
<para>Layer 3 can be configured to use <glossterm
baseform="Border Gateway Protocol (BGP)">BGP</glossterm>
confederation for scalability so core routers have state
proportional to the number of racks, not to the number of
servers or instances.</para>
</listitem>
<listitem>
@@ -200,14 +203,17 @@
means that an instance will also be on the same subnet as its
physical host. This means that it cannot be migrated outside
of the subnet easily. For these reasons, network
virtualization needs to use IP encapsulation and software at
virtualization needs to use IP <glossterm>encapsulation</glossterm>
and software at
the end hosts for both isolation, as well as for separation of
the addressing in the virtual layer from addressing in the
physical layer. Other potential disadvantages of layer 3
include the need to design an IP addressing scheme rather than
relying on the switches to automatically keep track of the MAC
addresses and to configure the interior gateway routing
protocol in the switches.</para></section></section>
protocol in the switches.</para>
</section>
</section>
<section xml:id="network-recommendations-overview">
<title>Network recommendations overview</title>
<para>OpenStack has complex networking requirements for several

3
doc/arch-design/specialized/section_networking_specialized.xml
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@@ -27,7 +27,8 @@
connectivity required to communicate via Intermediate
System-to-Intermediate System (ISIS) protocol or to pass
packets controlled via an OpenFlow controller. Using the
multiple layer 2 plug-in with an agent such as Open vSwitch
multiple layer 2 plug-in with an agent such as
<glossterm>Open vSwitch</glossterm>
would allow a private connection through a VLAN directly to a
specific port in a layer 3 device. This would allow a BGP
point to point link to exist that will join the autonomous

3
doc/arch-design/storage_focus/section_tech_considerations_storage_focus.xml
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@@ -30,7 +30,8 @@
<listitem>
<para>Scale: The scale of the storage solution in a
storage focused OpenStack architecture design is
driven both by initial requirements, including IOPS,
driven both by initial requirements, including
<glossterm>IOPS</glossterm>,
capacity, and bandwidth, as well as future needs.
Planning capacity based on projected needs over the
course of a budget cycle is important for a design.

237
doc/glossary/glossary-terms.xml
View File

@@ -40,6 +40,24 @@
OpenStack contribution process.
</para>
<glossdiv>
<title>Numbers</title>
<glossentry>
<glossterm>6to4</glossterm>
<indexterm class="singular">
<primary>6to4</primary>
</indexterm>
<glossdef>
<para>A mechanism that allows IPv6 packets to be transmitted
over an IPv4 network, providing a strategy for migrating to
IPv6.
</para>
</glossdef>
</glossentry>
</glossdiv>
<!-- .A. -->
<glossdiv>
@@ -558,9 +576,25 @@
</indexterm>
<glossdef>
<para>Companies that rent specialized applications that help
businesses and organizations provide additional services with less
cost.</para>
<para>
Companies that rent specialized applications that help
businesses and organizations provide additional services
with lower cost.
</para>
</glossdef>
</glossentry>
<glossentry>
<glossterm>Address Resolution Protocol (ARP)</glossterm>
<indexterm class="singular">
<primary>Address Resolution Protocol (ARP)</primary>
</indexterm>
<glossdef>
<para>
The protocol by which layer 3 IP addresses are resolved into
layer 2, link local addresses.
</para>
</glossdef>
</glossentry>
@@ -1059,7 +1093,7 @@
<glossterm>Bootstrap Protocol (BOOTP)</glossterm>
<indexterm class="singular">
<primary>Bootstrap Protocol (BOOTP)</primary>
</indexterm>
</indexterm>
<glossdef>
<para>A network protocol used by a network client to obtain an IP
@@ -1069,6 +1103,20 @@
</glossdef>
</glossentry>
<glossentry>
<glossterm>Border Gateway Protocol (BGP)</glossterm>
<indexterm class="singular">
<primary>Border Gateway Protocol (BGP)</primary>
</indexterm>
<glossdef>
<para>
The Border Gateway Protocol is a dynamic routing protocol
that connects autonomous systems. Considered the
backbone of the Internet, this protocol connects disparate
networks to form a larger network.</para>
</glossdef>
</glossentry>
<glossentry>
<glossterm>browser</glossterm>
<indexterm class="singular">
@@ -1094,6 +1142,21 @@
</glossdef>
</glossentry>
<glossentry>
<glossterm>bursting</glossterm>
<indexterm class="singular">
<primary>bursting</primary>
</indexterm>
<glossdef>
<para>
The practice of utilizing a secondary environment to
elastically build instances on-demand when the primary
environment is resource constrained.
</para>
</glossdef>
</glossentry>
<glossentry>
<glossterm>button class</glossterm>
<indexterm class="singular">
@@ -1919,6 +1982,22 @@
</glossdef>
</glossentry>
<glossentry>
<glossterm>content delivery network (CDN)</glossterm>
<indexterm class="singular">
<primary>content delivery network (CDN)</primary>
</indexterm>
<glossdef>
<para>
A content delivery network is a specialized network that is
used to distribute content to clients, typically located
close to the client for increased performance.
</para>
</glossdef>
</glossentry>
<glossentry>
<glossterm>controller node</glossterm>
<indexterm class="singular">
@@ -2259,6 +2338,22 @@
</glossdef>
</glossentry>
<glossentry>
<glossterm>Desktop-as-a-Service</glossterm>
<indexterm class="singular">
<primary>Desktop-as-a-Service</primary>
</indexterm>
<glossdef>
<para>
A platform that provides a suite of desktop environments
that users may log in to receive a desktop experience from
any location. This may provide general use, development, or
even homogenous testing environments.
</para>
</glossdef>
</glossentry>
<glossentry>
<glossterm>developer</glossterm>
<indexterm class="singular">
@@ -2755,6 +2850,21 @@
</glossdef>
</glossentry>
<glossentry>
<glossterm>encapsulation</glossterm>
<indexterm class="singular">
<primary>encapsulation</primary>
</indexterm>
<glossdef>
<para>
The practice of placing one packet type within another for
the purposes of abstracting or securing data. Examples
include GRE, MPLS, or IPsec.
</para>
</glossdef>
</glossentry>
<glossentry>
<glossterm>endpoint template</glossterm>
<indexterm class="singular">
@@ -3578,6 +3688,23 @@
</glossdef>
</glossentry>
<glossentry>
<glossterm>high availability (HA)</glossterm>
<indexterm class="singular">
<primary>high availability (HA)</primary>
</indexterm>
<glossdef>
<para>
A high availability system design approach and associated
service implementation ensures that a prearranged level of
operational performance will be met during a contractual
measurement period. High availability systems seeks to
minimize system downtime and data loss.
</para>
</glossdef>
</glossentry>
<glossentry>
<glossterm>horizon</glossterm>
@@ -3668,6 +3795,24 @@
</glossdef>
</glossentry>
<glossentry>
<glossterm>hybrid cloud</glossterm>
<indexterm class="singular">
<primary>hybrid cloud</primary>
</indexterm>
<glossdef>
<para>
A hybrid cloud is a composition of two or more clouds
(private, community or public) that remain distinct entities
but are bound together, offering the benefits of multiple
deployment models. Hybrid cloud can also mean the ability
to connect colocation, managed and/or dedicated services
with cloud resources.
</para>
</glossdef>
</glossentry>
<glossentry>
<glossterm>Hyper-V</glossterm>
<indexterm class="singular">
@@ -4226,6 +4371,24 @@
</glossdef>
</glossentry>
<glossentry>
<glossterm>IOPS</glossterm>
<indexterm class="singular">
<primary>IOPS</primary>
<secondary>definition of</secondary>
</indexterm>
<glossdef>
<para>
IOPS (Input/Output Operations Per Second) are a common
performance measurement used to benchmark computer storage
devices like hard disk drives, solid state drives, and
storage area networks.
</para>
</glossdef>
</glossentry>
<glossentry>
<glossterm>IP address</glossterm>
<indexterm class="singular">
@@ -4427,7 +4590,14 @@
</indexterm>
<glossdef>
<para>An OpenStack-supported hypervisor.</para>
<para>
An OpenStack-supported hypervisor. KVM is a full
virtualization solution for Linux on x86 hardware containing
virtualization extensions (Intel VT or AMD-V), ARM, IBM
Power, and IBM zSeries. It consists of a loadable kernel
module, that provides the core virtualization infrastructure
and a processor specific module.
</para>
</glossdef>
</glossentry>
@@ -4505,8 +4675,27 @@
</indexterm>
<glossdef>
<para>Term used for OSI network architecture for the data link
layer.</para>
<para>
Term used in the OSI network architecture for the data link
layer. The data link layer is responsible for media access
control, flow control and detecting and possibly correcting
erros that may occur in the physical layer.
</para>
</glossdef>
</glossentry>
<glossentry>
<glossterm>Layer-3 network</glossterm>
<indexterm class="singular">
<primary>Layer-3 network</primary>
</indexterm>
<glossdef>
<para>
Term used in the OSI network architecture for the network
layer. The network layer is responsible for packet
forwarding including routing from one node to another.
</para>
</glossdef>
</glossentry>
@@ -5524,6 +5713,24 @@
</glossdef>
</glossentry>
<glossentry>
<glossterm>Open vSwitch</glossterm>
<indexterm class="singular">
<primary>Open vSwitch</primary>
</indexterm>
<glossdef>
<para>
Open vSwitch is a production quality, multilayer virtual
switch licensed under the open source Apache 2.0 license. It
is designed to enable massive network automation through
programmatic extension, while still supporting standard
management interfaces and protocols (for example NetFlow,
sFlow, SPAN, RSPAN, CLI, LACP, 802.1ag).
</para>
</glossdef>
</glossentry>
<glossentry>
<glossterm>Open vSwitch neutron plug-in</glossterm>
<indexterm class="singular">
@@ -8451,6 +8658,22 @@
<glossdiv>
<title>X</title>
<glossentry>
<glossterm>Xen</glossterm>
<indexterm class="singular">
<primary>Xen</primary>
</indexterm>
<glossdef>
<para>
Xen is a hypervisor using a microkernel design, providing
services that allow multiple computer operating systems to
execute on the same computer hardware concurrently.
</para>
</glossdef>
</glossentry>
<glossentry>
<glossterm>Xen API</glossterm>