Coda File System

Re: Configuration for replicating servers

From: Guido Witmond <guido_at_lunatech.com>
Date: Wed, 5 Jul 2000 11:31:08 +0200
On Tue, Jul 04, 2000 at 09:30:41PM -0400, Jan Harkes wrote:
> On Tue, Jul 04, 2000 at 11:22:24AM -0700, Phil Nelson wrote:
> > 
> > >- Make two new entries in the /vice/db/VSGDB file. One for your new server
> > >  by itself, one of the form: E0000104 scm-server second-server. 
> > >I don't understand the 'One for your new server by itself' part here.
> > >I don't know what volume address to use, as my 2nd server does not have
> > >a root-volume of its own. Do I have to use the volume address of the
> > >root of the SCM? Or do I have to use a fake number?
> > 
> > The VSGDB defines "volume storage groups".  When volumes are created
> > via "createvol_rep", you specify a volume storage group, by number, for
> > where the volume is to be stored.  The numbers appear to be arbitrary (now)
> > but have historically started with E.......  Given your srv1 and srv2,
> > your VSGDB file might look like:

Thanks. This makes it clear to me. Some problems from the past can be
accounted to my experiments with the volume storage group numbers.
(giving both servers the vsg of server 1).
> 
> There is actually some code in the clients that relies on the VSGDB
> numbers to always start with E0. These numbers are hexadecimal encodings
> of multicast ip-addresses, although Coda does not use multicast ip.
> 
> > To help you here, we need some server logs.  I suspect that you have
> > run into a bug that has plagued me for some time ... a volume with
> > only one replica (that is stored only on one server) is running out of
> > room in the resolution log.  If this is the case, one possible fix is

In my early experiments I ran into a transaction log full message. But I
lost the logs.
> 
> That is very likely if the COP2 messages are missing. This happens often
> during (weak-)reintegration, and in normal cases the resolution logs are
> then truncated by a following resolution. However single replicated
> volumes do not ever develop a server-server conflict, so resolution is
> never triggered.

I've also seen messages regarding missing COP2, but they are also lost.
I will reinstall (very easy with debian packages) and try to reproduce
the error logs with lots of debugging enabled.

Greeting, Guido.
-- 
\-----------------------------------------------------------------------/
| Guido Witmond, guido_at_lunatech.com           Technical Nice Guy or so. |
|                                ----                                   |
| ``Poetic language (which we will henceforth designate by the letters  |
| 'pl') contains the code of linear logic, ''           Julia Kristeva  |
|                                ----                                   |
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Received on 2000-07-05 05:45:25