Hi Klas,
we are currently looking out for some kind of replication - your way of
doing it is interesting. However I would prefer a system where the
replication is completely transparent for dbmail mainly because of
postgresql/other database support: one of the main objectives of dbmail
is complete freedom for database choice as fas as dbmail is concerned.
Implementing this patch would break the symmetry giving extra
functionality only available with mysql.
Furthermore could you be more specific on your plan of recovery if one
of the machines crashes? Seems to me that you would have to rebuild
your dbmail system setting it up for 1 database.
Our plan for the moment is to have two databases: one used in
production and the other as hot spare. When the live machine is used,
the succesfull update/insert/delete queries are performed at the hot
spare as well (by means of some script running in the background). At
failure, all there is to do is change dbmail.conf and send a SIGHUP to
the daemons. This system has one major drawback: if the
update/insert/delete query fails on the hot spare but already has
succeeded on the production machine. We haven't figured this out
completely but then again: if the query fails probably something's
really wrong with the hot spare. What do you folks think about it?
Klas Handel heeft op vrijdag, 6 dec 2002 om 00:55 (Europe/Amsterdam)
het volgende geschreven:
Hi,
We're using dbmail together with MySQL. Since our database is quite
large and we have a lot of users we want to spread our load a little
bit. We have setup our database in replication (master/slave) mode.
Then what we want to do is force all read (select) activities to
our slave (slaves) and all write (delete, update and insert) to our
master database.
I've created a patch which does this (only MySQL). What you need to do
is #define the READ_DATABASE parameter in "db.h". Then there are some
addition parameters to be set in "dbmail.conf" (read_db, read_user
etc.).
If READ_DATABASE isn't defined dbmail should work as normal, i.e use
only one database.
I did create a patch earlier and sent it to the list, but it's not in
the
new release so it's probably nothing that people are interested in?
Still we are using it so I send it again...
(The patch version is the cvs from 2002-12-05)
Have a nice day!
/Klas
[EMAIL PROTECTED]
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