1.6/admin/ServersideInstallationVirtual.xml

   1 <?xml version="1.0" encoding="UTF-8"?>
   2 <chapter xmlns="http://docbook.org/ns/docbook" xmlns:xi="http://www.w3.org/2001/XInclude" xmlns:xl="http://www.w3.org/1999/xlink">
   3         <title>Installing In Virtualized <systemitem class="osname">Linux</systemitem> Environments</title>
   4         <section xml:id="serversideinstallation-virtual">
   5                 <title>Overview</title>
   6                 <para>This section describes the installation of Evergreen software in so-called "virtualized" software environments. Evergreen software runs as a native application on any of several well-known x86 (32-bit) and x86-64 (64-bit) <systemitem class="osname">Linux</systemitem> distributions including <systemitem class="osname">Ubuntu</systemitem> and <systemitem class="osname">Debian</systemitem> but it does not run as a native application on the <systemitem class="osname">Microsoft Windows</systemitem> operating system. However, it is possible to execute Evergreen on a <systemitem class="osname">Windows</systemitem> host system by running it within a virtual Linux-guest installation, which itself executes on the <systemitem class="osname">Windows</systemitem> system. The <systemitem class="osname">Linux</systemitem> environment is fully emulated and acts (within limits) just as if it were executing on a real standalone system.</para>
   7                 <para>This technique of emulating a <systemitem class="osname">Linux</systemitem> environment on a <systemitem class="osname">Windows</systemitem> host is a practical way to install and run an Evergreen system if it is not possible to dedicate a physical machine solely as a <systemitem class="osname">Linux</systemitem> host for Evergreen. This architecture is not recommended for large scale systems since there are performance limitations to running Evergreen in a virtualized environment. However, it is a reasonable architecture for smaller experimental systems, as a proof of concept, or as a conference-room pilot.</para>
   8                 <section>
   9                         <title>Installing Virtualization Software</title>
  10                         <para>As described above, Evergreen can be installed on top of an emulated <systemitem class="osname">Linux</systemitem> environment. The <systemitem class="osname">Linux</systemitem> environment, in turn, is installed on top of a software application such as <application>"VirtualBox"</application>, <application>"VMware"</application> or <application>"VirtualPC"</application> which must first be installed on the <systemitem class="osname">Windows</systemitem> system. This section contains step-by-step examples that show installing popular virtualization applications on a <systemitem class="osname">Windows</systemitem> host system. Following this section are further descriptions of installing <systemitem class="osname">Linux</systemitem> and Evergreen systems using that virtualization software.</para>
  11                         <section xml:id="serversideinstallation-virtual-vbox-install">
  12                                 <title>Installing <application>"VirtualBox"</application> Virtualization Software</title>
  13                                 <para>This section reviews installation of the <application>"VirtualBox"</application> application on <systemitem class="osname">WindowsXP Professional (SP2)</systemitem>. Download <application>VirtualBox</application> from their official website: <ulink url="http://download.virtualbox.org/virtualbox/3.2.8/VirtualBox-3.2.8-64453-Win.exe">http://download.virtualbox.org/virtualbox/3.2.8/VirtualBox-3.2.8-64453-Win.exe</ulink>, then run the executable file. Continue with the steps shown in the next five figures until the software has been successfully installed:</para>
  14                                 <figure>
  15                                         <title>Starting the Windows installation file</title>
  16                                         <mediaobject>
  17                                                 <imageobject>
  18                                                         <imagedata fileref="../media/serversideinstallation-virtual-vbox-install-1.png" scalefit="1" width="70%"/>
  19                                                 </imageobject>
  20                                         </mediaobject>
  21                                 </figure>
  22                                 <figure>
  23                                         <title>Welcome to <application>VirtualBox</application> setup wizard</title>
  24                                         <mediaobject>
  25                                                 <imageobject>
  26                                                         <imagedata fileref="../media/serversideinstallation-virtual-vbox-install-2.png" scalefit="1" width="70%"/>
  27                                                 </imageobject>
  28                                         </mediaobject>
  29                                 </figure>
  30                                 <figure>
  31                                         <title>Accept the license agreement</title>
  32                                         <mediaobject>
  33                                                 <imageobject>
  34                                                         <imagedata fileref="../media/serversideinstallation-virtual-vbox-install-3.png" scalefit="1" width="70%"/>
  35                                                 </imageobject>
  36                                         </mediaobject>
  37                                 </figure>
  38                                 <figure>
  39                                         <title>Waiting for files to be copied</title>
  40                                         <mediaobject>
  41                                                 <imageobject>
  42                                                         <imagedata fileref="../media/serversideinstallation-virtual-vbox-install-4.png" scalefit="1" width="70%"/>
  43                                                 </imageobject>
  44                                         </mediaobject>
  45                                 </figure>
  46                                 <figure>
  47                                         <title>Installation is complete</title>
  48                                         <mediaobject>
  49                                                 <imageobject>
  50                                                         <imagedata fileref="../media/serversideinstallation-virtual-vbox-install-5.png" scalefit="1" width="70%"/>
  51                                                 </imageobject>
  52                                         </mediaobject>
  53                                 </figure>
  54                         </section>
  55                         <section>
  56                                 <title>Installing <application>"VMware"</application> Virtualization Software</title>
  57                                 <para>This section reviews installation of the <application>"VMware"</application> application on <systemitem class="osname">WindowsXP Professional (SP2)</systemitem>. Download <application>VMware</application> from their official website: <ulink url="">link</ulink>, then run the executable file. Continue with the steps shown in the figures until the software has been successfully installed:</para>
  58                                 <figure>
  59                                         <title>Starting the Windows installation file</title>
  60                                         <mediaobject>
  61                                                 <imageobject>
  62                                                         <imagedata fileref="../media/serversideinstallation-virtual-vbox-install-1.png" scalefit="1" width="75%"/>
  63                                                 </imageobject>
  64                                         </mediaobject>
  65                                 </figure>
  66                                 <indexterm>
  67                                         <primary>ZZZ-REVIEW</primary>
  68                                         <secondary>ADD INFO ON VMWARE</secondary>
  69                                 </indexterm>
  70                                 <caution>ADD INFO ON VMWARE</caution>
  71                                 <para>At this point, <application>VirtualBox</application> has been installed, started for the first time, and a new virtual machine (VM) has been created. This VM is the environment in which the <systemitem class="osname">Linux</systemitem> / Evergreen installation will execute. Please continue in <xref linkend="serversideinstallation-virtual-install-linux-ev"/> with the installation of the <systemitem class="osname">Linux</systemitem> / Evergreen distribution.</para>
  72                         </section>
  73                         <section>
  74                                 <title>Installing <application>"VirtualPC"</application> Virtualization Software</title>
  75                                 <para>This section reviews installation of the <application>"VirtualPC"</application> application on <systemitem class="osname">WindowsXP Professional (SP2)</systemitem>. Download <application>VMware</application> from their official website: <ulink url="">link</ulink>, then run the executable file. Continue with the steps shown in the figures until the software has been successfully installed:</para>
  76                                 <figure>
  77                                         <title>Starting the Windows installation file</title>
  78                                         <mediaobject>
  79                                                 <imageobject>
  80                                                         <imagedata fileref="../media/serversideinstallation-virtual-vbox-install-1.png" scalefit="1" width="75%"/>
  81                                                 </imageobject>
  82                                         </mediaobject>
  83                                 </figure>
  84                                 <indexterm>
  85                                         <primary>ZZZ-REVIEW</primary>
  86                                         <secondary>ADD INFO ON VIRTUALPC</secondary>
  87                                 </indexterm>
  88                                 <caution>ADD INFO ON VIRTUALPC</caution>
  89                                 <para>At this point, <application>VirtualBox</application> has been installed, started for the first time, and a new virtual machine (VM) has been created. This VM is the environment in which the <systemitem class="osname">Linux</systemitem> / Evergreen installation will execute. Please continue in <xref linkend="serversideinstallation-virtual-install-linux-ev"/> with the installation of the <systemitem class="osname">Linux</systemitem> / Evergreen distribution.</para>
  90                         </section>
  91                 </section>
  92                 <section xml:id="serversideinstallation-virtual-install-linux-ev">
  93                         <title>Installing <systemitem class="osname">Linux</systemitem> / Evergreen on Virtualization Software</title>
  94                         <para>After the virtualization software is installed and running, there are two ways to continue with installing <systemitem class="osname">Linux</systemitem> and Evergreen software in the new virtualized environment:</para>
  95                         <orderedlist>
  96                                 <listitem>
  97                                         <para>Download and install a prebuilt software image that contains a working <systemitem class="osname">Linux</systemitem> / Evergreen system (see <xref linkend="serversideinstall-virtual-prebuilt"/> for details)</para>
  98                                 </listitem>
  99                                 <listitem>
 100                                         <para>Manually install a <systemitem class="osname">Linux</systemitem> guest system, then manually install Evergreen on it (see <xref linkend="serversideinstall-virtual-manual"/> for details)</para>
 101                                 </listitem>
 102                         </orderedlist>
 103                         <para>We review each method in the following sections.</para>
 104                         <section xml:id="serversideinstall-virtual-prebuilt">
 105                                 <title>Download and install a prebuilt software image</title>
 106                                 <para>You can download a prebuilt software image that, when installed with your virtualization software, emulates a <systemitem class="osname">Linux</systemitem> guest system containing a running Evergreen distribution. The image is essentially a snapshot of a hard disk from a fully configured, functional <systemitem class="osname">Linux</systemitem> system with Evergreen already installed.</para>
 107                                 <para>We recommend this approach if you wish to get Evergreen running quickly with minimal attention to configuration. After reviewing only a few configuration details you can have a working Evergreen system that integrates smoothly with the rest of your network. See <xref linkend="serversideinstall-virtual-versions"/> for a list of prebuilt software images that are currently available to download and install</para>
 108                                 <note>DISCLAIMER: The following virtual images have been contributed by members of the Evergreen community for the purposes of testing, evaluation, training, and development.</note>
 109                                 <table xml:id="serversideinstall-virtual-versions">
 110                                         <title>Linux / Evergreen Virtual Images</title>
 111                                         <tgroup align="left" cols="4" colsep="1" rowsep="1">
 112                                                 <thead>
 113                                                         <row>
 114                                                                 <entry>Linux Version</entry>
 115                                                                 <entry>Evergreen Version</entry>
 116                                                                 <entry>Image</entry>
 117                                                                 <entry>Comments</entry>
 118                                                         </row>
 119                                                 </thead>
 120                                                 <tbody>
 121                                                         <row>
 122                                                                 <entry>Debian lenny (5.0)</entry>
 123                                                                 <entry>1.6.0.1</entry>
 124                                                                 <entry>
 125                                                                         <ulink url="http://www.open-ils.org/~denials/Evergreen1601_DebianLenny.zip"> download </ulink>
 126                                                                 </entry>
 127                                                                 <entry>VirtualBox image</entry>
 128                                                         </row>
 129                                                         <row>
 130                                                                 <entry>Ubuntu karmic koala (9.10)</entry>
 131                                                                 <entry>1.6.0.0</entry>
 132                                                                 <entry>
 133                                                                         <ulink url="http://www.open-ils.org/~denials/Evergreen-1600-Karmic.zip"> download </ulink>
 134                                                                 </entry>
 135                                                                 <entry></entry>
 136                                                         </row>
 137                                                         <row>
 138                                                                 <entry>Ubuntu hardy heron (8.04)</entry>
 139                                                                 <entry>1.2.3.1</entry>
 140                                                                 <entry>
 141                                                                         <ulink url="http://open-ils.org/dokuwiki/doku.php?id=server:1.2:ubuntu804:readme"> download </ulink>
 142                                                                 </entry>
 143                                                                 <entry>VirtualBox image; no preloaded data</entry>
 144                                                         </row>
 145                                                         <row>
 146                                                                 <entry>Debian etch (4.0)</entry>
 147                                                                 <entry>1.2.2.3</entry>
 148                                                                 <entry>
 149                                                                         <ulink url="http://open-ils.org/dokuwiki/doku.php?id=vmware:debian"> download </ulink>
 150                                                                 </entry>
 151                                                                 <entry>VMware image; preloaded with 13,000 Gutenberg records</entry>
 152                                                         </row>
 153                                                         <row>
 154                                                                 <entry>Ubuntu gutsy gibbon (7.10)</entry>
 155                                                                 <entry>1.2.1.4</entry>
 156                                                                 <entry>
 157                                                                         <ulink url="http://www.open-ils.org/downloads/vmware/Evergreen_1.2.1.4_on_Ubuntu_7.10.zip"> download </ulink>
 158                                                                 </entry>
 159                                                                 <entry>VMware image</entry>
 160                                                         </row>
 161                                                         <row>
 162                                                                 <entry>Gentoo</entry>
 163                                                                 <entry>1.1.5</entry>
 164                                                                 <entry>
 165                                                                         <ulink url="http://www.open-ils.org/~denials/Evergreen_1.1.5_Gentoo_x86.zip"> download </ulink>
 166                                                                 </entry>
 167                                                                 <entry>VMware image</entry>
 168                                                         </row>
 169                                                 </tbody>
 170                                         </tgroup>
 171                                 </table>
 172                                 <indexterm>
 173                                         <primary>ZZZ-REVIEW</primary>
 174                                         <secondary>ADD LIST OF OTHER PREBUILT IMAGES</secondary>
 175                                 </indexterm>
 176                                 <caution>ADD LIST OF OTHER PREBUILT IMAGES</caution>
 177                                 <para>For the following example, we have already installed the <application>VirtualBox</application> application (see <xref linkend="serversideinstallation-virtual-vbox-install"/> for details). Continue with the steps as shown; refer to the accompanying figures for further information:</para>
 178                                 <procedure>
 179                                         <step>Start VirtualBox for the first time and select <menuchoice><guimenu>File</guimenu><guimenuitem>VirtualBox Media Manager</guimenuitem><guimenuitem>Add</guimenuitem></menuchoice> to locate the prebuilt software image just downloaded (the example shows it was extracted from the original <literal>.ZIP</literal> file into a temporary directory <literal>C:\temp</literal>). See <xref linkend="serversideinstallation-virtual-vm-install-2"/> for details.</step>
 180                                         <step>After selecting the file, click <guibutton>Open</guibutton> to import it (see <xref linkend="serversideinstallation-virtual-vm-install-3"/> for details).</step>
 181                                         <step>Then click <guibutton>OK</guibutton> to save the selection and return to the VirtualBox Media Manager (see <xref linkend="serversideinstallation-virtual-vm-install-4"/> for details).</step>
 182                                         <step>Click <guibutton>New</guibutton> to start the "Virtual Machine Wizard", then <guibutton>Next</guibutton> to continue and create a new virtual machine (VM) <xref linkend="serversideinstallation-virtual-vm-install-5"/>).</step>
 183                                         <step>Create a new name for the VM and set the operating system type, then click <guibutton>Next</guibutton> (see <xref linkend="serversideinstallation-virtual-vm-install-6"/>).</step>
 184                                         <step>Set the memory size (we chose the default value of 512Mb), then click <guibutton>Next</guibutton> (see <xref linkend="serversideinstallation-virtual-vm-install-7"/>).</step>
 185                                         <step>Edit the Virtual Hard Disk configuration settings; click the radio boxes "Boot Hard Disk" and "Use existing hard disk" and ensure that the disk name "Evergreen1601_DebianLenny.vmdk" is selected. Click <guibutton>Finish</guibutton> to finish the setup (see <xref linkend="serversideinstallation-virtual-vm-install-8"/>).</step>
 186                                         <step>
 187                                                 <para>Install the <application>VirtualBox Guest Additions</application> (really a required upgrade to VirtualBox)</para>
 188                                                 <indexterm>
 189                                                         <primary>ZZZ-REVIEW</primary>
 190                                                         <secondary>ADD INFO ON INSTALLING VIRTUALBOX GUEST ADDITIONS</secondary>
 191                                                 </indexterm>
 192                                                 <caution>ADD INFO ON INSTALLING VIRTUALBOX GUEST ADDITIONS</caution>
 193                                         </step>
 194                                         <step>Return to VirtualBox and see the summary of the VM just created. Click <guibutton>Start</guibutton> to boot the new VM (see <xref linkend="serversideinstallation-virtual-vm-install-9"/>).</step>
 195                                         <step>See the start of the <systemitem class="osname">Linux</systemitem> boot sequence. Choose "Debian Gnu/Linux, kernel 2.6.26-2-686" from the startup menu and type <guibutton>Enter</guibutton> to start <systemitem class="osname">Linux</systemitem> and Evergreen (see <xref linkend="serversideinstallation-virtual-vm-install-11"/>). After some delay you should see the command line prompt: <literal>debian-lenny login:</literal>  .  Log in with username <literal>root</literal> and password <literal>evergreen</literal> to continue (see <xref linkend="serversideinstallation-virtual-vm-install-14"/>).</step>
 196                                 </procedure>
 197                                 <para>At this point you have a running <systemitem class="osname">Linux</systemitem> / Evergreen system. If you need to modify the Evergreen configuration in any way, review the sectons of the standard Evergreen installation instructions in <xref linkend="serversideinstallation-ubuntudebian"/> that deal with configuration.</para>
 198                                 <figure xml:id="serversideinstallation-virtual-vm-install-2">
 199                                         <title>Starting <application>VirtualBox</application> for the first time</title>
 200                                         <mediaobject>
 201                                                 <imageobject>
 202                                                         <imagedata fileref="../media/serversideinstallation-virtual-vm-install-2.png" scalefit="1" width="70%"/>
 203                                                 </imageobject>
 204                                         </mediaobject>
 205                                 </figure>
 206                                 <figure xml:id="serversideinstallation-virtual-vm-install-3">
 207                                         <title>Selecting the software image in Virtual Media Manager</title>
 208                                         <mediaobject>
 209                                                 <imageobject>
 210                                                         <imagedata fileref="../media/serversideinstallation-virtual-vm-install-3.png" scalefit="1" width="70%"/>
 211                                                 </imageobject>
 212                                         </mediaobject>
 213                                 </figure>
 214                                 <figure xml:id="serversideinstallation-virtual-vm-install-4">
 215                                         <title>New software image added to <application>VirtualBox</application></title>
 216                                         <mediaobject>
 217                                                 <imageobject>
 218                                                         <imagedata fileref="../media/serversideinstallation-virtual-vm-install-4.png" scalefit="1" width="75%"/>
 219                                                 </imageobject>
 220                                         </mediaobject>
 221                                 </figure>
 222                                 <figure xml:id="serversideinstallation-virtual-vm-install-5">
 223                                         <title>Creating a new VM</title>
 224                                         <mediaobject><imageobject><imagedata fileref="../media/serversideinstallation-virtual-vm-install-5.png" scalefit="1" width="75%"/></imageobject>
 225 gg                                      </mediaobject>
 226                                 </figure>
 227                                 <figure xml:id="serversideinstallation-virtual-vm-install-6">
 228                                         <title>Setting the VM name and OS type</title>
 229                                         <mediaobject>
 230                                                 <imageobject>
 231                                                         <imagedata fileref="../media/serversideinstallation-virtual-vm-install-6.png" scalefit="1" width="75%"/>
 232                                                 </imageobject>
 233                                         </mediaobject>
 234                                 </figure>
 235                                 <figure xml:id="serversideinstallation-virtual-vm-install-7">
 236                                         <title>Setting memory size</title>
 237                                         <mediaobject>
 238                                                 <imageobject>
 239                                                         <imagedata fileref="../media/serversideinstallation-virtual-vm-install-7.png" scalefit="1" width="75%"/>
 240                                                 </imageobject>
 241                                         </mediaobject>
 242                                 </figure>
 243                                 <figure xml:id="serversideinstallation-virtual-vm-install-8">
 244                                         <title>Setting up the Virtual Hard Disk</title>
 245                                         <mediaobject>
 246                                                 <imageobject>
 247                                                         <imagedata fileref="../media/serversideinstallation-virtual-vm-install-8.png" scalefit="1" width="75%"/>
 248                                                 </imageobject>
 249                                         </mediaobject>
 250                                 </figure>
 251                                 <figure xml:id="serversideinstallation-virtual-vm-install-9">
 252                                         <title>Finishing definition of new VM</title>
 253                                         <mediaobject>
 254                                                 <imageobject>
 255                                                         <imagedata fileref="../media/serversideinstallation-virtual-vm-install-9.png" scalefit="1" width="75%"/>
 256                                                 </imageobject>
 257                                         </mediaobject>
 258                                 </figure>
 259                                 <figure xml:id="serversideinstallation-virtual-vm-install-10">
 260                                         <title>Summary of the new VM</title>
 261                                         <mediaobject>
 262                                                 <imageobject>
 263                                                         <imagedata fileref="../media/serversideinstallation-virtual-vm-install-10.png" scalefit="1" width="75%"/>
 264                                                 </imageobject>
 265                                         </mediaobject>
 266                                 </figure>
 267                                 <figure xml:id="serversideinstallation-virtual-vm-install-11">
 268                                         <title>Selecting VM from startup menu</title>
 269                                         <mediaobject>
 270                                                 <imageobject>
 271                                                         <imagedata fileref="../media/serversideinstallation-virtual-vm-install-11.png" scalefit="1" width="75%"/>
 272                                                 </imageobject>
 273                                         </mediaobject>
 274                                 </figure>
 275                                 <figure xml:id="serversideinstallation-virtual-vm-install-12">
 276                                         <title>Starting the new VM</title>
 277                                         <mediaobject>
 278                                                 <imageobject>
 279                                                         <imagedata fileref="../media/serversideinstallation-virtual-vm-install-12.png" scalefit="1" width="75%"/>
 280                                                 </imageobject>
 281                                         </mediaobject>
 282                                 </figure>
 283                                 <figure xml:id="serversideinstallation-virtual-vm-install-13">
 284                                         <title>Starting the new VM (continued)</title>
 285                                         <mediaobject>
 286                                                 <imageobject>
 287                                                         <imagedata fileref="../media/serversideinstallation-virtual-vm-install-13.png" scalefit="1" width="75%"/>
 288                                                 </imageobject>
 289                                         </mediaobject>
 290                                 </figure>
 291                                 <figure xml:id="serversideinstallation-virtual-vm-install-14">
 292                                         <title>Logging into the new VM</title>
 293                                         <mediaobject>
 294                                                 <imageobject>
 295                                                         <imagedata fileref="../media/serversideinstallation-virtual-vm-install-14.png" scalefit="1" width="75%"/>
 296                                                 </imageobject>
 297                                         </mediaobject>
 298                                 </figure>
 299                         </section>
 300                         <section xml:id="serversideinstall-virtual-manual">
 301                                 <title>Manually install <systemitem class="osname">Linux</systemitem> and Evergreen</title>
 302                                 <para>You can manually install a <systemitem class="osname">Linux</systemitem> guest system and Evergreen on your virtualization software.</para>
 303                                 <para>We recommend this approach if you need to specially configure either the <systemitem class="osname">Linux</systemitem> system or Evergreen itself. This will require a detailed review of both <systemitem class="osname">Linux</systemitem> and Evergreen configuration details. You are essentially doing a normal Evergreen installation on a <systemitem class="osname">Linux</systemitem> system; it just happens that <systemitem class="osname">Linux</systemitem> is running within a virtualized environment. Refer to <xref linkend="serversideinstallation-ubuntudebian"/> for information on the normal Evergreen installation, then continue with this section.</para>
 304                                 <para>For the following example, we have already installed the <application>VirtualBox</application> application (see <xref linkend="serversideinstallation-virtual-vbox-install"/> for details). Continue with the steps as shown; refer to the accompanying figures for further information:</para>
 305                                 <procedure>
 306                                         <step>
 307                                                 <para>Download and install a standard <systemitem class="osname">Ubuntu</systemitem> distribution in <application>"VirtualBox"</application>.</para>
 308                                                 <para>You can download a software image of a prebuilt <systemitem class="osname">Ubuntu</systemitem> distribution and immediately import it into <application>"VirtualBox"</application> , or you can download and install
 309 </para>
 310                                                 <indexterm>
 311                                                         <primary>ZZZ-REVIEW</primary>
 312                                                         <secondary>ADD DETAILS ON MANUAL INSTALLATION OF LINUX</secondary>
 313                                                 </indexterm>
 314                                                 <caution>ADD DETAILS ON MANUAL INSTALLATION OF LINUX</caution>
 315                                         </step>
 316                                         <step>
 317                                                 <para>Start (boot) <systemitem class="osname">Ubuntu</systemitem>.</para>
 318                                                 <indexterm>
 319                                                         <primary>ZZZ-REVIEW</primary>
 320                                                         <secondary>ADD DETAILS ON VM LINUX BOOT SEQUENCE</secondary>
 321                                                 </indexterm>
 322                                                 <caution>ADD DETAILS ON VM LINUX BOOT SEQUENCE</caution>
 323                                         </step>
 324                                         <step>
 325                                                 <para>Install Evergreen on <systemitem class="osname">Ubuntu</systemitem>.</para>
 326                                                 <indexterm>
 327                                                         <primary>ZZZ-REVIEW</primary>
 328                                                         <secondary>ADD DETAILS ON MANUAL INSTALLATION OF EVERGREEN</secondary>
 329                                                 </indexterm>
 330                                                 <caution>ADD DETAILS ON MANUAL INSTALLATION OF EVERGREEN</caution>
 331                                         </step>
 332                                 </procedure>
 333                                 <para>At this point, the <systemitem class="osname">Windows</systemitem> system is hosting an <systemitem class="osname">Ubuntu</systemitem> system, which itself is hosting the Evergreen distribution. So far as Evergreen is concerned, it is happily executing in a standard <systemitem class="osname">Ubuntu</systemitem> environment and behaves exactly as if it were executing on a standalone <systemitem class="osname">Ubuntu</systemitem> system.</para>
 334                                 <para>Of course, there are limitations to how well a virtualized <systemitem class="osname">Ubuntu</systemitem> system emulates a real one. The <application>"VirtualBox"</application> application itself consumes memory, and it contributes to the CPU load on the <systemitem class="osname">Windows</systemitem> host system. The emulated <systemitem class="osname">Ubuntu</systemitem> system will have less available memory and will execute more slowly than if it were a standalone system, therefore Evergreen itself will inherit some limitations from this overall environment.</para>
 335                                 <para>However, this technique of using a <systemitem class="osname">Windows</systemitem> host to emulate a <systemitem class="osname">Linux</systemitem> environment is a practical way to install and run an Evergreen system even if it isn't possible to dedicate a real machine solely as a <systemitem class="osname">Linux</systemitem> host for testing. This is a reasonable architecture for simple experiments, or as a proof of concept, or as a conference-room pilot.</para>
 336                         </section>
 337                 </section>
 338         </section>
 339         <index/>
 340 </chapter>