mirror of
https://github.com/ceph/ceph
synced 2024-12-18 09:25:49 +00:00
88 lines
3.5 KiB
ReStructuredText
88 lines
3.5 KiB
ReStructuredText
===============
|
|
Intro to Ceph
|
|
===============
|
|
|
|
Whether you want to provide :term:`Ceph Object Storage` and/or
|
|
:term:`Ceph Block Device` services to :term:`Cloud Platforms`, deploy
|
|
a :term:`Ceph Filesystem` or use Ceph for another purpose, all
|
|
:term:`Ceph Storage Cluster` deployments begin with setting up each
|
|
:term:`Ceph Node`, your network, and the Ceph Storage Cluster. A Ceph
|
|
Storage Cluster requires at least one Ceph Monitor, Ceph Manager, and
|
|
Ceph OSD (Object Storage Daemon). The Ceph Metadata Server is also
|
|
required when running Ceph Filesystem clients.
|
|
|
|
.. ditaa:: +---------------+ +------------+ +------------+ +---------------+
|
|
| OSDs | | Monitors | | Managers | | MDSs |
|
|
+---------------+ +------------+ +------------+ +---------------+
|
|
|
|
- **Monitors**: A :term:`Ceph Monitor` (``ceph-mon``) maintains maps
|
|
of the cluster state, including the monitor map, manager map, the
|
|
OSD map, and the CRUSH map. These maps are critical cluster state
|
|
required for Ceph daemons to coordinate with each other. Monitors
|
|
are also responsible for managing authentication between daemons and
|
|
clients. At least three monitors are normally required for
|
|
redundancy and high availability.
|
|
|
|
- **Managers**: A :term:`Ceph Manager` daemon (``ceph-mgr``) is
|
|
responsible for keeping track of runtime metrics and the current
|
|
state of the Ceph cluster, including storage utilization, current
|
|
performance metrics, and system load. The Ceph Manager daemons also
|
|
host python-based plugins to manage and expose Ceph cluster
|
|
information, including a web-based `dashboard`_ and `REST API`_. At
|
|
least two managers are normally required for high availability.
|
|
|
|
- **Ceph OSDs**: A :term:`Ceph OSD` (object storage daemon,
|
|
``ceph-osd``) stores data, handles data replication, recovery,
|
|
rebalancing, and provides some monitoring information to Ceph
|
|
Monitors and Managers by checking other Ceph OSD Daemons for a
|
|
heartbeat. At least 3 Ceph OSDs are normally required for redundancy
|
|
and high availability.
|
|
|
|
- **MDSs**: A :term:`Ceph Metadata Server` (MDS, ``ceph-mds``) stores
|
|
metadata on behalf of the :term:`Ceph Filesystem` (i.e., Ceph Block
|
|
Devices and Ceph Object Storage do not use MDS). Ceph Metadata
|
|
Servers allow POSIX file system users to execute basic commands (like
|
|
``ls``, ``find``, etc.) without placing an enormous burden on the
|
|
Ceph Storage Cluster.
|
|
|
|
Ceph stores data as objects within logical storage pools. Using the
|
|
:term:`CRUSH` algorithm, Ceph calculates which placement group should
|
|
contain the object, and further calculates which Ceph OSD Daemon
|
|
should store the placement group. The CRUSH algorithm enables the
|
|
Ceph Storage Cluster to scale, rebalance, and recover dynamically.
|
|
|
|
.. _dashboard: ../../mgr/dashboard
|
|
.. _REST API: ../../mgr/restful
|
|
|
|
.. raw:: html
|
|
|
|
<style type="text/css">div.body h3{margin:5px 0px 0px 0px;}</style>
|
|
<table cellpadding="10"><colgroup><col width="50%"><col width="50%"></colgroup><tbody valign="top"><tr><td><h3>Recommendations</h3>
|
|
|
|
To begin using Ceph in production, you should review our hardware
|
|
recommendations and operating system recommendations.
|
|
|
|
.. toctree::
|
|
:maxdepth: 2
|
|
|
|
Hardware Recommendations <hardware-recommendations>
|
|
OS Recommendations <os-recommendations>
|
|
|
|
|
|
.. raw:: html
|
|
|
|
</td><td><h3>Get Involved</h3>
|
|
|
|
You can avail yourself of help or contribute documentation, source
|
|
code or bugs by getting involved in the Ceph community.
|
|
|
|
.. toctree::
|
|
:maxdepth: 2
|
|
|
|
get-involved
|
|
documenting-ceph
|
|
|
|
.. raw:: html
|
|
|
|
</td></tr></tbody></table>
|