Coda File System

Re: Replication

From: Peter J. Braam <braam_at_cs.cmu.edu>
Date: Thu, 24 Sep 1998 10:26:00 -0400 (EDT)
On Thu, 24 Sep 1998, Image - Odinn Sorensen wrote:

> Hej Peter.
> 
> Wed 23 Sep 1998 12:12, "Peter J. Braam" <braam_at_cs.cmu.edu> wrote:
> 
>  PB> You need to define a volume storage group with the two servers in it.
> 
>  PB> Then run createvol_rep with that volume storage group.
> 
> Aha, I setup the SCM machine first and created volumes with createvol_rep.
> Then I setup the non-SCM machine, which I now can't get to replicate (or
> even start the server). How do I add servers to a VSG when the volume is
> already created?
> 
> So, I want to setup an SCM machine, create all the replicatable volumes I
> need on it, and then be able to add any number of additional replicating
> servers. I need the step-by-step guide to adding the additional servers.
> 

To get a second server going it needs to be added to the "servers" file on
the SCM and you need to create a VSG entry for it by itsel in the VSGDB
(volume storage group db). Then you can also create a VSG entry of the
form E000010?  server1 server2 and use that to make a replicated volume.  
Then, provided updateclnt etc are running on all hosts, it should start
and you should be able to get a replicated volume. 

The creavol_rep script goes by all the server hosts involved and asks them
to create a replica.  They then send databases back and these are
incorporated into a new master database for volumes at the scm.  The scm
then propagates this to all servers using updatesrv. I hope this
explains things a bit.

You cannot extend the volume storage group after the volume is created
(maybe in a future release). 

The manual has a lot of detail but it is not terribly well organised. I'd
love for a volunteer to make the instructions clearer - the src rpm (with
sgml text and formatting instructions is on the WWW).

- Peter -



> -- 
> Med venlig hilsen / Best Regards
>   Odinn Sørensen (System analyse og programmering) / Image Scandinavia A/S
>   Peter Bangs Vej 26, 2000 Frederiksberg, Denmark
>   Tlf. (+45) 38 14 70 00 - Fax (+45) 38 14 70 07
> 
Received on 1998-09-24 10:31:59