In this series of posts, I’m going to explore various reasons why you need Ceph storage in your infrastructure today. First, we’ll talk about Ceph block storage and why you should be using Ceph in building your public or private cloud infrastructures.
Some background basics: the base of all Ceph storage is called RADOS (Reliable Autonomic Distributed Object Store). RADOS provides a massively scalable object store that gives you data replication and intelligent data placement on commodity hardware. A Ceph cluster with RADOS consists of a number of object storage daemons (OSDs) and some monitor node daemons (MONs).
RADOS can be accessed in a number of ways, as shown in the diagram below. In future posts I will cover each of these in detail.
Ceph’s RADOS Block Device (RBD) is a thin-provisioned block device that is automatically striped across multiple OSDs in your cluster. Since it is built on top of RADOS, the block devices can be rapidly resized, snapshotted, and cloned. The data is also replicated according to policies that you define. And it’s integrated with libvirt/QEMU/KVM virtual clients. And it’s part of Linux: Ceph clients have been merged in the Linux kernel since 2010.
The Ceph Storage Architecture
So why is this cool? What does it mean for you? Why should you be using Ceph today?
If you’re running, or considering running, any of these:
- OpenStack
- CloudStack
- Citrix CloudPlatform
- SUSECloud
In any of these environments, you can use Ceph as a low-cost, massively scalable block storage platform to provide fast, thin-provisioned disk for all your virtual machines. You can also do this in any other environment that uses libvirt/QEMU/KVM virtual machines, or even physical Linux machines that need block storage.
This reduces your cost to deploy a cloud by a significant factor. You don’t need to purchase expensive proprietary block storage from a typical storage vendor. You get the speed, reliability and features you need like snapshots, cloning and thin provisioning, without the vendor lock-in. You get a storage system that runs on commodity hardware and which grows with you to exabyte scale as your cloud grows.
But that’s not all! You get a storage system that can then also provide object and filesystem storage when you need it. You get a passionate, active, open source community project with lots of resources. And you get a company that is dedicated to being the Ceph experts and providing exceptional support, services, and education when you need us.
Next time: Application-centric storage.
