[ale] MySql Replication

[Martha Armour]

I have a fail-over setup where two machines running
MySQL are slave/masters to each other; however,
the reserve machine does not do any updating of
the database and will only do so if it becomes
active.  To expand upon what Attriel said,
the auto increment tables will mess you up.  If
you try to insert a key that is already in an
auto incremented table, replication will break.

So for my setup, this is fine, but it won't work
correctly with two masters updating at the same
time.

- Martha

--- attriel <attriel at d20boards.net> wrote:
> > ------------------------
> > | Master In Alpharetta |
> > ------------------------
> >           |
> >           |
> >           |
> >   Slaves  |
> >   ----------------------
> >   |                    |
> >   Alpharetta        Buford
> >
> >
> > Is it possible to modify data in the slaves and
> > that data be modified in the master?  I
> > think I remeber that you had to allways
> > modify the master
> 
> AFAIR, no.  You have to modify the master, the
> slaves basically allow you
> to distribute querying (so, if you get a LOT of
> requests, but no so many
> updates) ...
> 
> For some of the stuff I'm trying to do, multi-master
> systems would be
> useful, and I remember talking to someone last year
> who said it was
> possible IF you add a new field for all tables
> "serverid" that is
> auto-filled by each server with it's own ID, then
> the uniqueness of
> whatever column is extended to include the serverid
> as well (b/c the
> auto-inc fields won't be unique anymore, since two
> servers might be
> serving at the same time)
> 
> Then there was some other problem with that scheme
> that I didn't follow
> (being why I haven't set this up yet :/)
> 
> If you get any more tips, let us know :)
> 
> --attriel


__________________________________
Do you Yahoo!?
SBC Yahoo! DSL - Now only $29.95 per month!
http://sbc.yahoo.com
_______________________________________________
Ale mailing list
Ale at ale.org
http://www.ale.org/mailman/listinfo/ale