Coda File System

Re: A new use for coda?

From: Zetas <zetas_at_gshellz.org>
Date: Fri, 23 Jul 2010 12:24:56 -0400 (EDT)
> Hello David,
>
> On Fri, Jul 23, 2010 at 10:40:24AM -0400, Zetas wrote:
>> A friend pointed me to coda and i started reading guides and how-to's and
>> began
>> setting it up on test boxes. As of now i have it "kinda" setup with clients
>> able
>> to connect and authenticate, add files, remove files, etc. BUT i think i have
>> something setup wrong somewhere, when i delete a file on one system, it doesnt
>> get deleted it other places even after waiting, sometimes files added dont
>> show
>
> It may depend on the inability of the clients to contact all the
> servers involved at the same time (which is necessary for proper
> reintegration / update propagation).
>
>> 3 servers: 1 thats the primary SCM and does nothing but house the files and
>> config, 1 in USA thats a client node and 1 in Europe thats also a client node.
>
> It looks like you have placed your servers geographically distantly from
> each other. This is actually "unsupported" as the design premises
> for Coda were that the servers have fast/reliable connections to
> each other.
>
>> My main question beyond the weird problems i'm having is, is my situation a
>> good
>> fit for coda?
>
> It depends on the expected usage pattern. Simultaneous access to a home
> directory from different client computers will most probably lead to
> reintegration conflicts and frustration and dissatisfaction as the result.
>
>> Does coda work well in a production environment where there is no
>> "lan" available?
>
> This depends on your definition of "well" and on the environment and the
> usage pattern.
>
> It is a special experience, having one's home directory on a file system
> with optimistic replication, especially if the user may happen to run
> processes on different client hosts at the same time. Many popular
> applications (like "bash", "less" or "mozilla") do not properly handle
> this in their default configuration or at all. The user needs to do some
> tricks and also be prepared to solve reintegration conflicts.
>
> I guess AFS may be a better fit as a general purpose file system
> for you. YMMV.
>
> I am routinely using a home directory on Coda and enjoy it but I would
> not recommend this to unprepared users. Advanced and experienced Coda
> users may consider such setup, with caution. Home directory makes one's
> logins highly vulnerable to problems with the underlying file system.
>
> Regards,
> Rune
>
>

Rune,

Thanks for your reply.

> It may depend on the inability of the clients to contact all the
> servers involved at the same time (which is necessary for proper
> reintegration / update propagation).

I see, i didnt realize they all had to reach each other, some of the clients im
using are behind firewalls.. makes sense now.
What ports and services would i need to allow in iptables or port forward in
routers to allow all clients access to each other?

> It looks like you have placed your servers geographically distantly from
> each other. This is actually "unsupported" as the design premises
> for Coda were that the servers have fast/reliable connections to
> each other.

They are both on 100Mbit connections and we also have a secured VPN between
them, its pretty reliable.

> It depends on the expected usage pattern. Simultaneous access to a home
> directory from different client computers will most probably lead to
> reintegration conflicts and frustration and dissatisfaction as the result.

We do not require simultaneous access, just in case one server goes down the
data is available on the other server for them to reconnect to.
We actually have resource limits in place that do not allow them to be connected
to or run processes on more then one server at a time.

Thanks,
David
Received on 2010-07-23 12:25:10