Coda File System

Re: Silly CODA questions

From: Jan Harkes <jaharkes_at_cs.cmu.edu>
Date: Tue, 14 Sep 1999 09:46:37 -0400
On Tue, Sep 14, 1999 at 02:05:44AM -0500, Christopher P. Lindsey wrote:
>    o How similar to Transarc's AFS is Coda?  I imagine that the commands
>      are close in terms of functionality, but probably differ in name
>      (I come from a strictly AFS background)

Not very similar, they both `originate' from about the same starting
point, but both have had several complete overhauls over the past 12
years.

>    o Does Coda interoperate with AFS cells?  The general answer appears 
>      to be no, but can I mount AFS volumes from within a Coda cell (and
>      if the authentication is different, can I use something icky like IP
>      acls as a hack?)

Not a chance, AFS uses RX for the rpc traffic, Coda uses RCP2/SFTP. Even
if you'd (manage to) replace the transport layer, the whole upper layer
interfaces are completely different. Coda servers have to provide
additional information, like version-vectors, so that clients can detect
replication and disconnected operation related conflicts.

Then there is the fs operation logging, (trickle)reintegration,
resolution, which all do not have an AFS equivalent. Also I believe,
AFS currently handles its cache on a block granularity, while Coda has
file-based granularity, which allow us to make certain consistency
guarantees.

>    o We have an existing Kerberos V realm in place.  Can Coda authenticate
>      to this directly, or do we need to create special per-user Coda
>      principals or modify the Kerberos database in any special ways?  Can
>      anyone direct me to K5 specific documentation?

There is an unexportable patch, which allows a user to get a Coda token
without typing a password if he is Kerberos authenticated.

>    o If using Kerberos V authentication, can we use Kerberos keytab files
>      to obtain tokens?  (this ties into the previous question) 

Likely, I haven't tried.

>    o How difficult is it to port AFS-aware code to work with Coda?  Is
>      the API similar, or is it another beast altogether?

It depends on what it is aware of, I never heard of this, probably
because I never asked :)

Jan
Received on 1999-09-14 10:08:02