mirror of
https://github.com/ceph/ceph
synced 2024-12-15 16:07:00 +00:00
103 lines
3.3 KiB
ReStructuredText
103 lines
3.3 KiB
ReStructuredText
=================
|
|
Welcome to Ceph
|
|
=================
|
|
|
|
Ceph is a distributed network storage and file system with distributed
|
|
metadata management and POSIX semantics.
|
|
|
|
RADOS is a reliable object store, used by Ceph, but also directly
|
|
accessible.
|
|
|
|
``radosgw`` is an S3-compatible RESTful HTTP service for object
|
|
storage, using RADOS storage.
|
|
|
|
RBD is a Linux kernel feature that exposes RADOS storage as a block
|
|
device. Qemu/KVM also has a direct RBD client, that avoids the kernel
|
|
overhead.
|
|
|
|
.. image:: overview.png
|
|
|
|
|
|
|
|
Mailing lists, bug tracker, IRC channel
|
|
=======================================
|
|
|
|
- `Ceph Blog <http://ceph.newdream.net/news/>`__: news and status info
|
|
- The development mailing list is at ceph-devel@vger.kernel.org, and
|
|
archived at Gmane_. Send email to subscribe_ or unsubscribe_.
|
|
- `Bug/feature tracker <http://tracker.newdream.net/projects/ceph>`__:
|
|
for filing bugs and feature requests.
|
|
- IRC channel ``#ceph`` on ``irc.oftc.net``: Many of the core
|
|
developers are on IRC, especially daytime in the US/Pacific
|
|
timezone. You are welcome to join and ask questions. You can find
|
|
logs of the channel `here <http://irclogs.ceph.widodh.nl/>`__.
|
|
- `Commercial support <http://ceph.newdream.net/support/>`__
|
|
|
|
.. _subscribe: mailto:majordomo@vger.kernel.org?body=subscribe+ceph-devel
|
|
.. _unsubscribe: mailto:majordomo@vger.kernel.org?body=unsubscribe+ceph-devel
|
|
.. _Gmane: http://news.gmane.org/gmane.comp.file-systems.ceph.devel
|
|
|
|
|
|
Status
|
|
======
|
|
|
|
The Ceph project is currently focusing on stability. Users are
|
|
welcome, but we do not recommend storing valuable data with it yet
|
|
without proper precautions.
|
|
|
|
As of this writing, RADOS is the most stable component, and RBD block
|
|
devices are fairly reliable, if not performance tuned yet. The OSD
|
|
component of RADOS relies heavily on the stability and performance of
|
|
the underlying filesystem, and we keep hearing reports of ``btrfs``
|
|
issues; while on the long term we believe in ``btrfs``, in the short
|
|
term you may wish to carefully consider the tradeoffs between ``ext4``
|
|
and ``btrfs``, and make sure you are running the latest Linux kernel.
|
|
|
|
Radosgw is still going through heavy development, but it will likely
|
|
mature next.
|
|
|
|
.. _cfuse-kernel-tradeoff:
|
|
|
|
The Ceph filesystem is functionally fairly complete, but has not been
|
|
tested well enough at scale and under load yet. Multi-master MDS is
|
|
still problematic and we recommend running just one active MDS
|
|
(standbys are ok). If you have problems with ``kclient`` or ``ceph-fuse``,
|
|
you may wish to try the other option; in general, ``kclient`` is
|
|
expected to be faster (but be sure to use the latest Linux kernel!)
|
|
while ``ceph-fuse`` provides better stability by not triggering kernel
|
|
crashes.
|
|
|
|
As individual systems mature enough, we move to improving their
|
|
performance (throughput, latency and jitter). This work is still
|
|
mostly ahead of us.
|
|
|
|
Ceph is developed on Linux. Other platforms may work, but are not the
|
|
focus of the project. Filesystem access from other operating systems
|
|
can be done via NFS or Samba re-exports.
|
|
|
|
|
|
Table of Contents
|
|
=================
|
|
|
|
.. toctree::
|
|
:maxdepth: 3
|
|
|
|
start/index
|
|
architecture
|
|
ops/index
|
|
rec/index
|
|
config
|
|
api/index
|
|
Internals <dev/index>
|
|
man/index
|
|
papers
|
|
appendix/index
|
|
|
|
|
|
Indices and tables
|
|
==================
|
|
|
|
- :ref:`genindex`
|
|
- :ref:`search`
|
|
|