Ask Your Question

Why Swift is required in Openstack?

asked 2014-11-27 23:44:00 -0600

Hi I could successfully configure Openstack with Glance and Cinder. Images are getting stored in Glance and Volumes are getting stored in Cinder. Now I can provide Instances and manage them successfully. Now I am still unclear about Necessary of Swift storage in this setup. What is the purpose of Swift Storage ?

edit retag flag offensive close merge delete

1 answer

Sort by ยป oldest newest most voted

answered 2014-11-28 00:28:33 -0600

updated 2015-07-23 00:30:29 -0600

Swift is an object-storage system to store files and large objects on the cloud using simple APIs. Swift converts every files and objects stored on the cloud to the specifil URL(like:, that your application can retrive files using simple http requests. But in order to use swift in your deployment, your running applications must be cloud-ready application(Cloud-ready means the app is written in a way to use cloud APIs specially swift APIs in this case, or atleast use swift file URLs to retrieve files from cloud instead of local storage). Traditional apps, can not leverage facilities provided by swift, becasue they store/retrive files using operating system APIs.

You didn't need swift becasue your applications are legacy apps that store their files and objects on the local attached virtual disk(provided by cinder), using OS file system APIs instead of cloud storage system(Swift). So, you didn't feel the need of swift.

In summery swift can be used in the following ways:

  • Use as Glance backend to store Images(image is considred as object)
  • Store/Retreive files and objects by cloud-ready applications using swift APIs
  • Store/Retrive cloud backup archives

Hope to be useful.

edit flag offensive delete link more


Thanks Very much. Yes it is more clear. Can I use Swift for replicating Cinder and Glance across different regions then?

NeeleshG gravatar imageNeeleshG ( 2014-11-28 00:49:05 -0600 )edit

What was the mean of different regions in your comment? Geographically difference(multi-site) or different zone in same location(datacenter)?

Mzoorikh gravatar imageMzoorikh ( 2014-11-28 01:00:24 -0600 )edit

Geographically defferent Regions (Multi-Site).

NeeleshG gravatar imageNeeleshG ( 2014-11-28 01:18:05 -0600 )edit

As I said, swift can be backend for Glance but not for cinder. Cinder use other storage backends such as LVM, GlusterFS, ZFS, Ceph, etc. Yes it is possible to use Swift to replicate Glance image storage backend, into multipe sites in geographically difference. See here.

Mzoorikh gravatar imageMzoorikh ( 2014-11-28 01:50:12 -0600 )edit

Thanks very much for your help.

NeeleshG gravatar imageNeeleshG ( 2014-11-28 02:06:50 -0600 )edit

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Get to know Ask OpenStack

Resources for moderators

Question Tools

1 follower


Asked: 2014-11-27 23:44:00 -0600

Seen: 283 times

Last updated: Jul 23 '15