From ddd1617a74308a7a22e0317ccd1679c72f82fb0a Mon Sep 17 00:00:00 2001 From: Philip Schwartz Date: Mon, 15 Jun 2015 14:49:22 -0400 Subject: [PATCH] Added documentation around database upgrades Listed the current process for upgrading the Nova database to allow for better understanding of what will be changing. Change-Id: Ib1c6abd8b08fe0987e2535d0ed6729f5384cebf3 Signed-off-by: Philip Schwartz --- doc/source/upgrade.rst | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) diff --git a/doc/source/upgrade.rst b/doc/source/upgrade.rst index b2de32de933a..91bf2591adb1 100644 --- a/doc/source/upgrade.rst +++ b/doc/source/upgrade.rst @@ -29,6 +29,40 @@ This document is trying to describe how we can achieve that. Once we have introduced the key concepts relating to upgrade, we will introduce the process needed for a no downtime upgrade of nova. + +Current Database Upgrade Types +------------------------------ + +Currently Nova has 2 types of database upgrades that are in use. + +#. Offline Migrations +#. Online Migrations + + +Offline Migrations consist of: +'''''''''''''''''''''''''''''' + + #. Database schema migrations from pre-defined migrations in + nova/db/sqlalchemy/migrate_repo/versions. + + #. *Deprecated* Database data migrations from pre-defined migrations in + nova/db/sqlalchemy/migrate_repo/versions. + + +Online Migrations consist of: +''''''''''''''''''''''''''''' + + #. Online data migrations from inside Nova object source code. + + #. *Future* Online schema migrations using auto-generation from models. + + +An example of online data migrations are the flavor migrations done as part +of Nova object version 1.18. This included a transient migration of flavor +storage from one database location to another. + +:emphasis:`Note: Database downgrades are not supported.` + Concepts --------