https://habrahabr.ru/company/performix/blog/218065/
https://sohabr.net/habr/post/313644/
http://efsol.ru/articles/storage-system.html
http://blog.in-a-nutshell.ru/ceph-issues-in-firstvds-and-lessons-learned/
http://ceph.com/community/500-osd-ceph-cluster/