June 16, 2011 OpenStack Conference: Blocks and Volumes Notes
I’m continuing the several-weeks-late rundown on the OpenStack Conference. Previously, I walked through my OpenStack Conference Networking discussion notes. This time I’ll be sharing my notes from the block storage / volume sessions I attended. I hopped through most of the sessions as best I could. Here is my summary.
XenAPI Volume Driver
Renuka Apte of Citrix proposed adding a new Xen-specific volume driver in Nova (alongside the existing iSCSI, AoE drivers) that would make callouts to XenAPI. The proposal was basically a proposal to allow Nova to piggyback off of their existing XenAPI Storage Manager. This would add support for NFS, NetApp, various iSCSI / FC, EqualLogic, etc. It does add an additional layer of abstraction to volume management, but it does open the door for broader storage support for those using XenServer.
Gluster talked us through their clustered filesystem and shared how various companies are using their solution. Their OpenStack proposal was to provide Swift-compatible APIs and to provide image storage. It could potentially be an interesting blend of an object store with filesystem access. Mostly it felt like they wanted to share the work that they have been doing on their open-source (with commercial offering) clustered filesystem and introduce themselves to the OpenStack community.
Virtual Storage Arrays
A new company in stealth mode made their appearance at the conference. Their goal is to create virtual volumes that end-users can carve up into partitions however they would like, with the performance characteristics that they would like. For example, compute instances are available with many different performance characteristics (Sizing is along the dimension of RAM, CPU cores, IO capabilities, etc.). Zadara wants to provide the ability to specify performance characteristics (IO, durability, etc.) to block storage so that a cloud can provide storage blocks along more dimensions than just gigabytes.
Chuck Thier of Rackspace presented the block-storage service called Lunr. Presumably, we can expect to see the results of this soon from Rackspace Cloud Servers. Lunr is a separate block storage service with its own set of OpenStack APIs. Below is the blueprint for its integration into Nova. https://blueprints.launchpad.net/nova/+spec/integrate-block-storage
Snapshot/Clone/Boot from Volume
Isaku Yamahata of VA Linux, Japan and Kazutaka Morita of NTT were also are working on an EBS-equivalent system. They modified Nova-volume itself to allow for snapshots, cloning, and boot from volumes. They’ve implemented a proof-of-concept based on the EC2 APIs and just using LVM2. The Lunr project will probably superseded this effort.
In Summary, expect to see Lunr API support in Diablo. Watch for software storage vendors to provide out-of-the-box support for the Lunr API. I expect the next OpenStack Conference to have session discussing where next to take Lunr to support more features.
See Previous: OpenStack Conference Spring 2011 Networking