Category Archives: OpenStack

Upgrades in Nova: Database Migrations

This is a part of a series of posts on the details of how Nova supports live upgrades. It focuses on one of the more complicated pieces of the puzzle: how to do database schema changes with minimal disruption to … Continue reading

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Upgrades in Nova: Objects

This is a part of a series of posts on the details of how Nova supports live upgrades. It focuses on a very important layer that plays several roles in the system, providing a versioned RPC and database-independent facade for … Continue reading

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Upgrades in Nova: RPC APIs

This is a part of a series of posts on the details of how Nova supports live upgrades. It focuses on the very important task of doing proper versioning and handling compatibility in your RPC APIs, which is a baseline … Continue reading

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Upgrades in Nova: The Details

Over the last few years, the Nova project has spent a lot of time on improving its story around live upgrades. We’ve made a lot of progress and done so with minimal disruption as we were figuring out how to … Continue reading

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Upgrading Nova to Kilo with minimal downtime

Starting in Icehouse, Nova gained the ability to do partial live upgrades. This first step meant that control services (which are mostly stateless) could be upgraded along with database schema before any of the compute nodes. After that step was … Continue reading

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A brief overview of Nova’s new object model (Part 3)

In parts one and two, I talked about the reasoning for developing an object model inside of Nova, as well as showed a sample implementation for a toy object. In this part, I will examine parts of some “real” objects … Continue reading

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A brief overview of Nova’s new object model (Part 2)

In Part 1, I described the problems that the Unified Object Model aims to solve within Nova. Next, I’ll describe how the infrastructure behind the scenes achieves some of the magic of making things easier for developers to implement their … Continue reading

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A brief overview of Nova’s new object model (Part 1)

As discussed at the Havana summit, I have been working with Chris Behrens (and others) on the unified-object-model blueprint for Nova. The core bits of it made their way into the tree a while ago and work is underway to … Continue reading

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A tool for watching Zuul and Jenkins

In my work on OpenStack Nova, I often have multiple patches in flight somewhere on the CI system. When patches are first submitted (or resubmitted) they go into Zuul’s “check” queue for a first pass of the tests. After a … Continue reading

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Dan’s Partial Summary of the Nova Track

Last week, OpenStack developers met in Portland, OR for the Havana Design Summit. Being mostly focused on Nova development, I spent almost all of my time in that track. Below are some observations not yet covered by other folks. Baremetal … Continue reading

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