openstack-manuals/doc/config-reference/compute/section_compute-conductor.xml
Gauvain Pocentek 590bb27b37 update nova flags and tables
Removed docker references (the driver has been removed from nova).

Update confilcting pages including tables to use xrefs instead.

Add a rpc_all section to handle conflicts in the training-guides.

Closes-Bug: #1291138
Closes-Bug: #1292612
Change-Id: I67ad31c3913cae4c2e9e3d2ce41302717af5d839
2014-03-23 07:41:52 +01:00

44 lines
2.4 KiB
XML

<?xml version="1.0" encoding="UTF-8"?>
<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="section_conductor">
<title>Conductor</title>
<para>The <systemitem class="service">nova-conductor</systemitem>
service enables OpenStack to function without compute nodes
accessing the database. Conceptually, it implements a new
layer on top of <systemitem class="service"
>nova-compute</systemitem>. It should not be deployed on
compute nodes, or else the security benefits of removing
database access from <systemitem class="service"
>nova-compute</systemitem> are negated. Just like
other nova services such as <systemitem class="service"
>nova-api</systemitem> or nova-scheduler, it can be scaled
horizontally. You can run multiple instances of <systemitem
class="service">nova-conductor</systemitem> on different
machines as needed for scaling purposes.</para>
<para>In the Grizzly release, the methods exposed by <systemitem
class="service">nova-conductor</systemitem> are relatively
simple methods used by <systemitem class="service"
>nova-compute</systemitem> to offload its database
operations. Places where <systemitem class="service"
>nova-compute</systemitem> previously performed database
access are now talking to <systemitem class="service"
>nova-conductor</systemitem>. However, we have plans in
the medium to long term to move more and more of what is
currently in <systemitem class="service"
>nova-compute</systemitem> up to the <systemitem
class="service">nova-conductor</systemitem> layer. The
Compute service will start to look like a less intelligent
slave service to <systemitem class="service"
>nova-conductor</systemitem>. The conductor service will
implement long running complex operations, ensuring forward
progress and graceful error handling. This will be especially
beneficial for operations that cross multiple compute nodes,
such as migrations or resizes.</para>
<para>To customize the Conductor, use the configuration option settings
documented in <xref linkend="config_table_nova_conductor"/>.</para>
</section>