Coda File System

Re: Come-and-go system with data replication

From: Lionix <lio_at_absium.com>
Date: Mon, 27 Oct 2003 22:40:32 +0100
josef.schwarz_at_bt.com wrote:

>Hi,
>
>I'm playing around with Coda now for the third week and I really don't know if I head to the right direction. I would like to have a "public" directory for <50 nodes, where everyone (with permission) can read/write. 
>
Just set acl that permit it....

>The data that a node stores on the network, shall be also available, when the node goes offline. 
>
Coda's volume replication feather...

>That means I need my data redundant on two or more servers 
>
Two servers minimum for redundance...

>(in case the client is at the same time server). 
>
Coda-Server and coda-client are really distinct... but you can install a 
client on a server .

>Additionally it is a come-and-go system, so when a server goes offline, another one must be started and so on (so that f.e. always 3 servers are online). I thought, it should be possible with some scripting and some monitoring to have the appropriate files copied and the daemons started. 
>
No you have to let the two servers started, running, in order them to 
replicate all data....
When one is down for a while, everything work corectly because there is 
still one up that could hang the work...
And when the down server get back up, he will syncronize and  get all 
new data automaticaly...

>I think a server needs to be restarted when another one is added, so it's probably better to have only two or three servers in the network (probably with Coda it's not possible for all nodes to work at a client and server at the same time). 
>
Don't understand.... sorry...

>I don't want to rely on caching, because also new clients should get access to all files.
>I have tried to get a clue of how to use rootvolumes, additional volumes, replication and so on, but I'm seriously afraid, I need advice, how to structure such a system with Coda.
>  
>
First of all :

- STOP thinking in IP... you are going in such a complicated way for a 
couple of day , getting aroud modifying conf files / commands !! I 
really think you are in a wrong way of work...  Try to make it work 
correctly,  before modifying things and go into  no-ways !
( there is enough to do !!! )

Just have a look at you last email :

'cfs lv /coda/172.16.1.1' and 'cfs lv /coda/172.16.3.1'

That mean you have two clusters !!!!!

And you are trying to set up  :
- 1 cluster of two server
- a /coda/my_first_cluster-realm_name/public/  directory...
with /public that would be a volume replicated on 172.16.1.1 and 
172.16.3.1 no ???

Did you succeed in creating a replicated volumes ???

Perhaps the better advice  : I think you'd better start again from 
scratch.....
Your are such in a complicated way that you had mis-understand the 
concept, and certainly some commands....
Moreover i think there will probably be part of the coda-code that don't 
work because you have a "fancy" configuration !

Hang on.... read a lot...  Google(tm) and the mailing list archive is 
your best friend...
Everybody  get difficulties at the begining... but you can overcome !!!!

Lionix
FS-cluster ( newbee ? ) Administrator
Hundreds hours of work... but so powerfull !!!!

http://www.absium.com
Received on 2003-10-27 16:57:24