第1章 The Shared File Systems service with CephFS through NFS
With the Shared File Systems service (manila) with Ceph File System (CephFS) through NFS, you can use the same Ceph cluster that you use for block and object storage to provide file shares through the NFS protocol. For more information, see Configuring the Shared File Systems service (manila) in the Storage Guide.
The RHOSP Shared File Systems service with CephFS through NFS for RHOSP 16.0 and later is supported for use with Red Hat Ceph Storage version 4.1 or later. For more information about how to determine the version of Ceph Storage installed on your system, see Red Hat Ceph Storage releases and corresponding Ceph package versions.
CephFS is the highly scalable, open-source distributed file system component of Red Hat Ceph Storage, a unified distributed storage platform. Ceph Storage implements object, block, and file storage using Reliable Autonomic Distributed Object Store (RADOS). CephFS, which is POSIX compatible, provides file access to a Ceph storage cluster.
The Shared File Systems service (manila) enables users to create shares in CephFS and access them with NFS 4.1 through NFS-Ganesha. NFS-Ganesha controls access to the shares and exports them to clients through the NFS 4.1 protocol.
The Shared File Systems service manages the life cycle of these shares from within RHOSP. When cloud administrators configure the service to use CephFS through NFS, these file shares come from the CephFS cluster, but are created and accessed as familiar NFS shares.
For more information about the Shared File Systems service, see Configuring the Shared File Systems service (manila) in the Storage Guide.
1.1. CephFS with native driver
The CephFS native driver combines the OpenStack Shared File Systems service (manila) and Red Hat Ceph Storage. When you use Red Hat OpenStack (RHOSP) director, the Controller nodes host the Ceph daemons, such as the manager, metadata servers (MDS), and monitors (MON) and the Shared File Systems services.
Compute nodes can host one or more projects. Projects, which were formerly referred to as tenants, are represented in the following graphic by the white boxes. Projects contain user-managed VMs, which are represented by gray boxes with two NICs. To access the ceph and manila daemons projects, connect to the daemons over the public Ceph storage network.
On this network, you can access data on the storage nodes provided by the Ceph Object Storage Daemons (OSDs). Instances, or virtual machines (VMs), that are hosted on the project boot with two NICs: one dedicated to the storage provider network and the second to project-owned routers to the external provider network.
The storage provider network connects the VMs that run on the projects to the public Ceph storage network. The Ceph public network provides back end access to the Ceph object storage nodes, metadata servers (MDS), and Controller nodes.
Using the native driver, CephFS relies on cooperation with the clients and servers to enforce quotas, guarantee project isolation, and for security. CephFS with the native driver works well in an environment with trusted end users on a private cloud. This configuration requires software that is running under user control to cooperate and work correctly.