Getting Started With Celeste
It takes a few steps to get going, but once they are completed you will be able to keep up-to-date with the latest version of Celeste from the code repository, and build and experiment on your own.
- Obtain and install a copy of the mercurial source code management system.
- Create a directory on your local filesystem to contain the Celeste sources.
- In a terminal window, change the current directory to the directory you created to contain the Celeste sources and execute the mercurial command line:
hg clone ssh://anon@hg.opensolaris.org/hg/celeste/trunk
Celeste is a high availability peer-to-peer data store with semantics for file creation, arbitrary read and write, and deletion.
As in similar systems, Celeste divides file data into blocks and replicates each block on multiple nodes in the system. Celeste dynamically caches and re-caches block replicas to ensure that a minimum number of them exist in the system to protect against loss and that all the blocks are available to recover the entire data file. Celeste clients create, write, and subsequently read files despite the fact that some of the nodes, and consequently some of the blocks, may be unavailable.
In contrast to many other systems, Celeste clients are able to update data files and delete them. Clients may update any portion of a file and Celeste keeps changes coherent despite multiple simultaneous readers and writes, and arbitrary node failures. Data is deleted completely, even in the face of node failures and absence. Celeste clients work with data files using a full complement of operations: create, delete, read, write, and administrative controls such as access control and the concept of a file namespace.
Celeste originated as Sun Microsystems Laboratories research project investigating techniques for building large scale, distributed storage systems that work not only in dedicated data centers but also in open and potentially hostile environments such as the Internet.
While the system is demonstrable, Celeste is still very much a work-in-progress. The Sun Labs team, comprised of Glenn Scott, the Sun Labs Principal Investigator for Celeste, and Glenn Skinner, lending his experience in systems design and development, are working full-time on Celeste and continue to meet, discuss, and develop new code and concepts for Celeste, its users and developers. Our goal is to expand Celeste into the areas of distributed processing and storage using the foundation developed. We invite other developers, users and researchers to consider Celeste as a platform for their own applications, extensions and further work.
