Synnefo » snf-ganeti » ganeti-local

      </para>

      <para>There are four types of disk template you can choose from:

      <variablelist>

        <varlistentry>

          <term>diskless</term>

	  <listitem><para>The instance has no disks. Only used for special

	  purpouse operating systems or for testing.</para></listitem>

        </varlistentry>

        <varlistentry>

          <term>plain</term>

	  <listitem><para>The instance will use LVM devices as backend for its

	  disks. No redundancy is provided.</para></listitem>

        </varlistentry>

        <varlistentry>

          <term>local_raid1</term>

	  <listitem><para>A local mirror is set between LVM devices to back the

	  instance. This provides some redundancy for the instance's

	  data.</para></listitem>

        </varlistentry>

        <varlistentry>

          <term>remote_raid1</term>

	  <listitem><para>A mirror is set between the local node and a remote

	  one, which must be specified with the --secondary-node option. Use

	  this option to obtain a highly available instance that can be failed

	  over to a remote node should the primary one fail.

	  </para></listitem>

        </varlistentry>

      </variablelist>

      For example if you want to create an highly available instance use the

      remote_raid1 disk template:

      <para>Do not use the xen commands to stop instances. If you run for

      example xm shutdown or xm destroy on an instance Ganeti will

      automatically restart it (via the

      <citerefentry><refentrytitle>ganeti-watcher</refentrytitle>

      <manvolnum>8</manvolnum></citerefentry>)

      </para>

	If you want to add a device later you can do so with the 

	<citerefentry><refentrytitle>vgextend</refentrytitle>

	<manvolnum>8</manvolnum></citerefentry> command.