How exactly are Distributed File Systems used in cloud environment ?
More precisely:
- Are live VMs images (or their filesystem) usually located in the DFS ?
- Are VMs usually used to run the backbone (actual code) of DFS structure ?
Precise example citing DFS (ceph, Gluster, GFS, GPFS, Lustre) or cloud environment (Openstack , CloudStack, ...) would be appreciated, even if I'm more interested by ceph on OpenStack for now.
I couldn't find real life example, and all this is very new for me and very confusing. I know pretty well LXC and linux administration (except from cloud solution). I went through ceph quick starting guide, and requirements. Read papers on Openstack and viewed presentation videos.
juju has charms to setup ceph, but juju can administer LXC on local machine as well as instances on cloud services from amazon or openstack and these are often VMs. But aren't these cloud services needing a DFS for their own services ? This is where it becomes quite confusing for me. And as I guess that the answer might be different for different solutions, I would like some precise example citing DFS or cloud environment involved with the given answer.