Coda File System

Re: conflict repair

From: <braam_at_cs.cmu.edu>
Date: Fri, 13 Nov 1998 10:45:52 -0500 (EST)
Hi Michael,

The global conflicts are conflicts among servers.  You will not see
these until you have a second server.  Local global conflicts are
those between a client and  server(s).  You can get these through disconnection. 

In each case there are several types of conflicts, some affect
directories (and often then the files in them too).  An example of a
directory conflict is the creation of two files with the same names,
from two disconnected clients.  All such directory conflicts are to be
repaired with repair.  You could print out Puneet Kumar's thesis
(somewhere on our WWW site) and learn about the precise classes of
conflicts.  The directory conflicts come in a limited but complicated
variety and repair's main task is to analyze which happened and
present them to the user.

A simpler type of conflict arises from storing the same file twice.
For example doing echo a>>file on workstation 1 and echo b>>file on
workstation 2 will give a pure file conflict.  [note that editors
often do not modify files in place but re-create files upon saving, so
their behaviour is more complicated than this].  These conflicts can
be repaired with the egasr repair tools, which are MUCH simpler.
Still for them a nice gui would be most useful too.

To repair your current conflict, you should use repair (make sure you
have tokens) and simply discardalllocal when it is offered.  Then do
the cat tricks and try filerepair.

It sounds to me that you have made good progress, since you are now
almost at the point of being able to start your work.

- Peter -



Michael Stone writes:
 > Quoting braam_at_cs.cmu.edu (braam_at_cs.cmu.edu):
 > > I suggest that we first concentrate on file repair. Those utilities
 > > are in coda-src/egasr and are fairly easy to understand (I recommend
 > > you look at the source).
 > 
 > Well, I have file repair working with the 'repair' tool, but 'xfrepair' tells
 > me "hosts has a local/global conflict, please use the regular repair tool".
 > Does that mean that xfrepair only works on server/server conflicts? (I.e., do
 > I need two servers to try this?)
 > 
 > Mike Stone
Received on 1998-11-13 10:52:20