> 1) I have searched this mailing-list and I understood that Qmail can
> handle this demand very nicely, right? Are those patches for "high
> load servers" really necessary or is the default qmail distribution
> (with concurrencyremote set to 100 or something) enough?
They're there for a reason...of course, these presume that your link can
handle a greater concurrency.
> 2) Whats the best way to send the 500,000 mails? Send a single
> message with 500,000 destination addresses or to send 500,000
> messages, one for each email address?
One message with 500,000 destination addresses. Could you imagine opening up
500,000 smtp connections to a single server? Uh uh.
> 3) If I really need to send 500,000 different messages (for custom
> text inside the message) to the users, will this stress Qmail or will
> it handle it okay?
qmail won't have a problem. But how big is your server? Your server will
likely cack it if you send 500,000 messages from another machine. My best
advice? Generate a template with metatags in it (like <name>, <company>),
have a database ready, and run it through a perl script that calls
qmail-inject.
If you don't need to customise messages, consider using ezmlm-idx. It will
remove addresses that bounce after 14 days if they can't be resolved, it is
easy to administer, users can subscribe and unsubscribe at whim, it can me
moderated so messages can't be sent to the mailing list unless you authorise
them to be...
/BR
Manager
InterPlanetary Solutions
http://ipsware.com/
