CephCephFS

Introduction

Three ways to access storage: Object, Block, File

Object RGW Block RBD File: CephFS

Object storage: scles well. simple consistancy model, one object at a time, clients are simple, to replationships between objects, one name per object, scale out achieved through mapping objects to nodes

POSIX filesystems are hard to scale out, due to lcocking, multiple clients accessing the same file, clients are stateful, loss of data and damage whole subtree, inodes depend on each other,

CephFS - Dynamically balcance scale out meta data, POSIX compatability, subtree snapshots, recursive stats CephFS components: client, server (MDS), storage (OSD)