[Dbbalancer-users] Re: Request for comments

[Andrew M. <an...@ca...>]

On Tue, 2001-11-06 at 09:40, Daniel Varela Santoalla wrote:
> On Sun 04 Nov 2001 00:13, you wrote:
> 
> > The idea I have so far is:
> >
> > 1) Have a directory of configuration scripts for the various databases
> > to be 'balanced'.  I would make this directory in /etc/dbbalancer/conf.d
> > which would conform to the way Debian does these sorts of things.
> >
> > 2) My init script would then go through each configuration file in the
> > directory, starting a DBBalancer daemon for each one.
> 
> I see a problem with this one. The "reader" or "writer" operation is not 
> thought to be extracted from the configuration file, as this file should be 
> shared between a reader and a writer. The difference was in the "-r" or "-w" 
> parameter. Maybe it could be better to use different config files for the 
> reader and the writer, but they share almost all parameters (except for the 
> port)... We have to find the best solution for this...

Good point.  Would it be possible to add a parameter into the
configuration file which overrode the default, but was in turn
overridden by the command line?

Alternatively, I could have my script use something of the configuration
file name, so that files xxxxx.conf were readers and xxxxx-w.conf were
writes.  Crude, but workable.

One gotcha I found writing my script is that DBBalancer checks that it's
configuration file ends in ".conf" - I don't think that this check is
really necessary.



> > 3) The process ID for each process would be written in
> > /var/run/dbbalancer/<confname>
> 
> I'll have to make this path configurable, just like the UNIX socket path has 
> to be.

I have the above scheme working under Debian by specifying the pidfile
name as a parameter to the start-stop-daemon command.  It works now, but
there would be differences if the Daemon was writing it's own pidfile.



> Well. I fully agree with the last three. The others are also good, but maybe 
> I have to change the way "readers" and "writers" are differentiated. Not a 
> big problem, anyway.

I can't wait :-)

Thanks,
					Andrew.
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