Coda File System

Using Coda for server mirroring (in lieu of rsync)

From: Andy Sy <>
Date: Sun, 19 Jul 2009 05:29:21 +0800
We have a web server setup which we want to
mirror and load-balance.  We basically want to
be able to synchronize the contents of the
htdocs/ directories on two or more different
servers in [more or less] real time.

The common approach would be to have rsync running
on each server copying the most recent version of a
file over to the server(s) that do not yet have it
every few minutes (invoked via cron).

I feel that rsync is really a rather clunky approach
and I was wondering, is Coda a suitable and much better
alternative in this scenario?

Based on my surface reading of how Coda works (forgive
me if I have any egregious misconceptions), in the simplest
case of 2 servers "mirroring" each other, the setup would be
a Vice file server process running on each of the 2 servers,
as well as a Venus process on each providing the
htdocs/ mount.

Would the above be a reasonable, recommended setup?

I am guessing the operation would work very roughly
something like the below:

Updating htdocs/* while connected to server A would naturally
update server A's Vice copy of htdocs/ first which would then
transparently get replicated over to server B's copy eventually.

In a case where server B's Vice process happens to be down, but
with everything else still up, server B's htdocs/ would get
served from/by server A's Vice process transparently?

In the case where server A and B's Vice processes are both
up, accessing htdocs/ would be effectively be nearly as
fast as access to to a, say, normal ext3 mount?
Received on 2009-07-18 17:51:03