From 48d5d5639431884478c30db3c9c986fb98205c9c Mon Sep 17 00:00:00 2001
From: Dmitry Tantsur <dtantsur@protonmail.com>
Date: Tue, 18 Jun 2019 16:48:03 +0200
Subject: [PATCH] Document storage backends and migrating between them

Change-Id: I36e5a9b9faf59684adf807c2a065c35a5d4a00f6
---
 doc/source/admin/upgrade.rst | 13 +++++++++++++
 doc/source/install/index.rst | 16 ++++++++++++++++
 2 files changed, 29 insertions(+)

diff --git a/doc/source/admin/upgrade.rst b/doc/source/admin/upgrade.rst
index 3ad72aff4..e953dfdb5 100644
--- a/doc/source/admin/upgrade.rst
+++ b/doc/source/admin/upgrade.rst
@@ -26,3 +26,16 @@ When upgrading ironic-inspector, the following steps should always be taken:
 .. note::
     There is no implicit upgrade order between ironic and ironic-inspector,
     unless the `release notes`_ say otherwise.
+
+Migrating introspection data
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Starting with Stein release, ironic-inspector supports two introspection data
+storage backends: ``swift`` and ``database``. If you decide to change the
+backend, you can use the provided command to migrate the data::
+
+    ironic-inspector-migrate-data --from swift --to database --config-file /etc/ironic-inspector/inspector.conf
+
+.. note::
+    Configuration for **both** backends is expected to be present in the
+    configuration file for this command to succeed.
diff --git a/doc/source/install/index.rst b/doc/source/install/index.rst
index 1c32add46..08d60c489 100644
--- a/doc/source/install/index.rst
+++ b/doc/source/install/index.rst
@@ -98,6 +98,22 @@ Fill in these minimum configuration values:
 * if you wish to use the ``dnsmasq`` PXE/DHCP filter driver rather than the
   default ``iptables`` driver, see the :ref:`dnsmasq_pxe_filter` description.
 
+* ``store_data`` in the ``processing`` section defines where introspection data
+  is stored and takes one of three values:
+
+  ``none``
+    introspection data is not stored (the default)
+  ``database``
+    introspection data is stored in the database (recommended for standalone
+    deployments)
+  ``swift``
+    introspection data is stored in the Object Store service (recommended for
+    full openstack deployments)
+
+  .. note::
+    It is possible to create third party storage backends using the
+    ``ironic_inspector.introspection_data.store`` entry point.
+
 See comments inside :doc:`the sample configuration
 </configuration/sample-config>` for other possible configuration options.