Coda File System

Coda Distributed File System

From: Peter J. Braam <>
Date: Wed, 18 Jun 1997 08:54:15 -0400 (EDT)
Coda Filesystem version 4.0.5

The Alpha release of Coda for Linux is finally there! RPMS are available

Also get the INSTALL and CHANGES.linux files.

Coda is an advanced networked file system developed at CMU in the group of
M. Satyanarayanan.  Coda boasts features such as:

- disconnected operation for laptops
- read/write server replication
- high performance through persistent caching on the client
- solid security model 
- continued operation during server network partitioning
- bandwith adaptation
- good scalability
- good semantics for sharing
- Coda is freely available

There is a very active group at CMU developing Coda further.  We expect to
do more ports, increase performance through write back caching,
incorporate Kerberos, do careful profiling and provide better tools for
administration.  In the longer run we hope to have a LDAP browseable cell
model. The Coda project hopes to make Coda widely accepted and available
during the next years.

WARNING:  Coda is alpha software.  It contains kernel code and servers
running with root priviliges.  Use Coda at your own risk.

You can play with the client and use a publicly available test server at

We can reliably build kernels and Coda using Linux Coda fileservers for
storage, and run Linux Wabi Microsoft Office apps all hoarded in
disconnected mode on Linux laptops. Despite the fact that no profiling has
been done for a long time, we have reasonable performance.  

Our main Coda cluster has mostly Mach 2.6 servers (for which Coda was
originally developed) and NetBSD and Linux servers (towards which we are
moving). We have both Linux and NetBSD affectionados in the group. We have
some 40 clients and use Coda for our daily work. Most of our volumes are
triply replicated.  

More information on Coda can be found at 
Coda's ancestor is AFS version 2, but each went different ways more around
10 years ago. 

There are a few nice Linux kernel support projects which could help Coda.
If you want to do some kernel hacking let me know.  If you want to
contribute to Coda otherwise (ports to Sparc Linux and AXP Linux would be
really neat!) please contact me and I'll try to assist. 

Copying: Coda comes under a BSD style license issued by CMU.  The Linux
Coda kernel code is gpld.   Contributions to the core of Coda should all
be made under the BSD style license, Linux specific kernel work can be
GPLD.  Coda must remain free. 

Peter J. Braam

Senior Systems Scientist
Coda Project, 
Computer Science Department, 
Carnegie Mellon University
Received on 1997-06-18 09:16:51