Ceph was developed at University of California, Santa Cruz, by Sage Weil in 2003 as a part of his PhD project. The initial project prototype was the Ceph filesystem, written in approximately 40,000 lines of C++ code, which was made open source in 2006 under a Lesser GNU Public License (LGPL) to serve as a reference implementation and research platform. Lawrence Livermore National Laboratory supported Sage's initial research work. The period from 2003 to 2007 was the research period of Ceph. By this time, its core components were emerging, and the community contribution to the project had begun at pace. Ceph does not follow a dual licensing model, and has no enterprise-only feature set.

In late 2007, Ceph was getting mature and was waiting to get incubated. At this point, DreamHost, a Los-Angeles-based web hosting and domain registrar company entered the picture. DreamHost incubated Ceph from 2007 to 2011. During this period, Ceph was gaining its shape; the existing components were made more stable and reliable, various new features were implemented, and future roadmaps were designed. Here, the Ceph project became bona fide with enterprise options and roadmaps. During this time, several developers started contributing to the Ceph project; some of them were Yehuda Sadeh, Weinraub, Gregory Farnum, Josh Durgin, Samuel Just, Wido den Hollander, and Loïc Dachary, who joined the Ceph bandwagon.

In April 2012, Sage Weil founded a new company, Inktank, which was funded by DreamHost. Inktank was formed to enable the widespread adoption of Ceph's professional services and support. Inktank is the company behind Ceph whose main objective is to provide expertise, processes, tools, and support to their enterprise-subscription customers, enabling them to effectively adopt and manage Ceph storage systems. Sage was the CTO and Founder of Inktank. In 2013, Inktank raised $13.5 million in funding. On April 30, 2014, Red Hat, Inc.—the world's leading provider of open source solutions—agreed to acquire Inktank for approximately $175 million in cash. Some of the customers of Inktank include Cisco, CERN, and Deutsche Telekom, and its partners include Dell and Alcatel-Lucent, all of which will now become the customers and partners of Red Hat for Ceph's software-defined storage solution. For more information, please visit www.inktank.com.

The term Ceph is a common nickname given to pet octopuses; Ceph can be considered as a short form for Cephalopod, which belongs to the mollusk family of marine animals. Ceph has octopuses as its mascot, which represents Ceph's parallel behavior to octopuses.

The word Inktank is somewhat related to cephalopods. Fishermen sometimes refer to cephalopods as inkfish due to their ability to squirt ink. This explains how cephalopods (Ceph) have some relation with inkfish (Inktank). Likewise, Ceph and Inktank have a lot of things in common. You can consider Inktank to be a thinktank for Ceph.