On Fri, Jun 15, 2012 at 12:03:55PM +0800, Adam Bradley wrote:
> Given I now know you can't achieve the approach above I'll pursue using a
> lookup table. However, with around 5 million users, address verification
> was looking like the best option.
No, a lookup table scales much better.
> My only concern is scalability, is there anything you can point me to
> regarding transport_maps and sizing/scalability?
Use a lookup table. You can use CDB, PgSQL, LDAP, MySQL or Berkeley
DB. With Berkeley DB you should always rebuild the database in a
separate file and then rename the new file. Concurrent updates of
Postfix Berkeley DB tables while are not completely safe, there is
a small probability of readers using inconsistent data.
5,000,000 records is not a lot of data, but the update rate may
be 1000's a day, and so a database (PgSQL, LDAP, ...) may be the
better choice, but try CDB, if that meets your needs, it is must
simpler, and likely faster. You can safelky rsync CDB files from
a master copy if that's useful.
--
Viktor.
