openstack-manuals/doc/install-guide/section_nova-compute-install.xml

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<section xmlns="http://docbook.org/ns/docbook"
  xmlns:xi="http://www.w3.org/2001/XInclude"
  xmlns:xlink="http://www.w3.org/1999/xlink"
  version="5.0"
  xml:id="nova-compute-install">
  <title>Install and configure a compute node</title>
  <para>This section describes how to install and configure the Compute
    service on a compute node. The service supports several
    <glossterm baseform="hypervisor">hypervisors</glossterm> to
    deploy <glossterm baseform="instance">instances</glossterm> or
    <glossterm baseform="virtual machine (VM)">VMs</glossterm>. For simplicity,
    this configuration uses the
    <glossterm baseform="Quick EMUlator (QEMU)">QEMU</glossterm> hypervisor
    with the
    <glossterm baseform="kernel-based VM (KVM)">KVM</glossterm> extension
    on compute nodes that support hardware acceleration for virtual machines.
    On legacy hardware, this configuration uses the generic QEMU hypervisor.
    You can follow these instructions with minor modifications to horizontally
    scale your environment with additional compute nodes.</para>
  <procedure os="ubuntu;rhel;centos;fedora;sles;opensuse">
    <title>To install and configure the Compute hypervisor components</title>
    <step>
      <para>Install the packages:</para>
      <screen os="ubuntu"><prompt>#</prompt> <userinput>apt-get install nova-compute</userinput></screen>
      <screen os="rhel;centos;fedora"><prompt>#</prompt> <userinput>yum install openstack-nova-compute</userinput></screen>
      <screen os="sles;opensuse"><prompt>#</prompt> <userinput>zypper install openstack-nova-compute</userinput></screen>
    </step>
    <step>
      <para>Edit the <filename>/etc/nova/nova.conf</filename> file and
        complete the following actions:</para>
      <substeps>
        <step>
          <para>In the <literal>[database]</literal> section, configure
            database access:</para>
          <programlisting language="ini">[database]
...
connection = mysql://nova:<replaceable>NOVA_DBPASS</replaceable>@<replaceable>controller</replaceable>/nova</programlisting>
          <para>Replace <replaceable>NOVA_DBPASS</replaceable> with the password
            you chose for the Compute database.</para>
        </step>
        <step>
          <para>In the <literal>[DEFAULT]</literal> section, configure
            <application>RabbitMQ</application> message broker access:</para>
          <programlisting language="ini">[DEFAULT]
...
rpc_backend = rabbit
rabbit_host = <replaceable>controller</replaceable>
rabbit_password = <replaceable>RABBIT_PASS</replaceable></programlisting>
          <para>Replace <replaceable>RABBIT_PASS</replaceable> with the password
            you chose for the <literal>guest</literal> account in
            <application>RabbitMQ</application>.</para>
        </step>
        <step>
          <para>In the <literal>[keystone_authtoken</literal>] section,
            configure Identity service access:</para>
         <programlisting language="ini">
[keystone_authtoken]
...
auth_uri = http://<replaceable>controller</replaceable>:5000/v2.0
auth_host = <replaceable>controller</replaceable>
auth_port = 35357
auth_protocol = http
admin_tenant_name = service
admin_user = nova
admin_password = <replaceable>NOVA_PASS</replaceable></programlisting>
          <para>Replace <replaceable>NOVA_PASS</replaceable> with the password
            you chose for the <literal>nova</literal> user in the Identity
            service.</para>
        </step>
        <step>
          <para>In the <literal>[DEFAULT]</literal> section, configure the
            <literal>my_ip</literal> key:</para>
          <programlisting language="ini">[DEFAULT]
...
my_ip = <replaceable>MANAGEMENT_INTERFACE_IP_ADDRESS</replaceable></programlisting>
          <para>Replace
            <replaceable>MANAGEMENT_INTERFACE_IP_ADDRESS</replaceable> with
            the IP address of the management network interface on your
            first compute node, typically 10.0.0.31 in the
            <link linkend="architecture_example-architectures">example
            architecture</link>.</para>
        </step>
        <step>
          <para>In the <literal>[DEFAULT]</literal> section, enable and
            configure remote console access:</para>
          <programlisting language="ini">[DEFAULT]
...
vnc_enabled = True
vncserver_listen = 0.0.0.0
vncserver_proxyclient_address = <replaceable>MANAGEMENT_INTERFACE_IP_ADDRESS</replaceable>
novncproxy_base_url = http://<replaceable>controller</replaceable>:6080/vnc_auto.html</programlisting>
          <para>The server component listens on all IP addresses and the proxy
            component only listens on the management interface IP address of
            the compute node. The base URL indicates the location where you
            can use a web browser to access remote consoles of instances
            on this compute node.</para>
          <para>Replace
            <replaceable>MANAGEMENT_INTERFACE_IP_ADDRESS</replaceable> with
            the IP address of the management network interface on your
            first compute node, typically 10.0.0.31 in the
            <link linkend="architecture_example-architectures">example
            architecture</link>.</para>
          <note>
            <para>If the web browser to access remote consoles resides on a
              host that cannot resolve the
              <replaceable>controller</replaceable> hostname, you must replace
              <replaceable>controller</replaceable> with the management
              interface IP address of the controller node.</para>
          </note>
        </step>
        <step>
          <para>In the <literal>[DEFAULT]</literal> section, configure the
            location of the Image Service:</para>
          <programlisting language="ini">[DEFAULT]
...
glance_host = <replaceable>controller</replaceable></programlisting>
        </step>
      </substeps>
    </step>
  </procedure>
  <procedure os="debian">
    <title>To install and configure the Compute hypervisor components</title>
    <step>
      <para>Install the packages:</para>
      <screen><prompt>#</prompt> <userinput>apt-get install nova-compute</userinput></screen>
    </step>
    <step>
      <para>Respond to the prompts for
        <link linkend="debconf-dbconfig-common">database management</link>,
        <link linkend="debconf-keystone_authtoken">Identity service
        credentials</link>,
        <link linkend="debconf-api-endpoints">service endpoint
        registration</link>, and
        <link linkend="debconf-rabbitmq">message broker
        credentials.</link>.</para>
    </step>
  </procedure>
  <procedure>
    <title>To finalize installation</title>
    <step>
      <para>Determine whether your compute node supports hardware acceleration
        for virtual machines:</para>
      <screen><prompt>$</prompt> <userinput>egrep -c '(vmx|svm)' /proc/cpuinfo</userinput></screen>
      <para>If this command returns a value of
        <emphasis>one or greater</emphasis>, your compute node supports
        hardware acceleration which typically requires no additional
        configuration.</para>
      <para>If this command returns a value of <emphasis>zero</emphasis>,
        your compute node does not support hardware acceleration and you must
        configure <literal>libvirt</literal> to use QEMU instead of KVM.</para>
      <substeps>
        <step>
          <para>Edit the <literal>[libvirt]</literal>
            section in the
            <filename os="ubuntu;debian">/etc/nova/nova-compute.conf</filename>
            <filename os="rhel;centos;fedora;sles;opensuse"
              >/etc/nova/nova.conf</filename> file as follows:</para>
          <programlisting language="ini">[libvirt]
...
virt_type = qemu</programlisting>
          <warning os="ubuntu">
            <para>On Ubuntu 12.04, kernels backported from newer releases may
              not automatically load the KVM modules for hardware acceleration
              when the compute node boots. In this case, launching an instance
              will fail with the following message in the
              <filename>/var/log/nova/nova-compute.log</filename> file:</para>
            <screen><computeroutput>libvirtError: internal error: no supported architecture for os type 'hvm'</computeroutput></screen>
            <para>As a workaround for this issue, you must add the appropriate
              module for your compute node to the
              <filename>/etc/modules</filename> file.</para>
            <para>For systems with Intel processors:</para>
            <screen><prompt>#</prompt> <userinput>echo 'kvm_intel' >> /etc/modules</userinput></screen>
            <para>For systems with AMD processors:</para>
            <screen><prompt>#</prompt> <userinput>echo 'kvm_amd' >> /etc/modules</userinput></screen>
          </warning>
        </step>
      </substeps>
    </step>
    <step os="ubuntu;debian">
      <para>Restart the Compute service:</para>
      <screen><prompt>#</prompt> <userinput>service nova-compute restart</userinput></screen>
    </step>
    <step os="rhel;centos;fedora;sles;opensuse">
      <para>Start the Compute service including its dependencies and configure
        them to start automatically when the system boots:</para>
      <stepalternatives os="rhel;centos;fedora">
        <step>
          <para>For RHEL, CentOS, and compatible derivatives:</para>
          <screen><prompt>#</prompt> <userinput>service libvirtd start</userinput>
<prompt>#</prompt> <userinput>service messagebus start</userinput>
<prompt>#</prompt> <userinput>service openstack-nova-compute start</userinput>
<prompt>#</prompt> <userinput>chkconfig libvirtd on</userinput>
<prompt>#</prompt> <userinput>chkconfig messagebus on</userinput>
<prompt>#</prompt> <userinput>chkconfig openstack-nova-compute on</userinput></screen>
        </step>
        <step>
          <para>For Fedora:</para>
          <screen><prompt>#</prompt> <userinput>service libvirtd start</userinput>
<prompt>#</prompt> <userinput>service dbus start</userinput>
<prompt>#</prompt> <userinput>service openstack-nova-compute start</userinput>
<prompt>#</prompt> <userinput>chkconfig libvirtd on</userinput>
<prompt>#</prompt> <userinput>chkconfig dbus on</userinput>
<prompt>#</prompt> <userinput>chkconfig openstack-nova-compute on</userinput></screen>
        </step>
      </stepalternatives>
      <screen os="opensuse;sles"><prompt>#</prompt> <userinput>service libvirtd start</userinput>
<prompt>#</prompt> <userinput>chkconfig libvirtd on</userinput>
<prompt>#</prompt> <userinput>service openstack-nova-compute start</userinput>
<prompt>#</prompt> <userinput>chkconfig openstack-nova-compute on</userinput></screen>
    </step>
    <step os="ubuntu">
      <para>By default, the Ubuntu packages create an SQLite database.</para>
      <para>Because this configuration uses a SQL database server, you can
        remove the SQLite database file:</para>
      <screen><prompt>#</prompt> <userinput>rm /var/lib/nova/nova.sqlite</userinput></screen>
    </step>
  </procedure>
</section>