|
Hi,
I have been using qmail for the last year and a
half and have been closely following the mailing list at securepoint, and didn't
find anything related to my query, hence I took the liberty of posting
it.
The objective is to build a high-volumer server
capable of doing mail-merged email blasts to several lists with 10,000 to
1,000,000 users, provide detailed reports about the status of emails (sent,
bounced, bad email addresses, opened, forwarded), list management (across
multiple lists for each user) and of course, stability.
Over the period of last 12 months, we explored
several options - and finally settled on qmail (what else?). I am using a
Pentium III with Linux Redhat 6.2 installed on it, with 512 MB of RAM, 20 GB HDD
and JDK 1.2.2 connected to a 128 Kbps line.
Following are the topics on which I need your
comments/suggestions:-
1. Earlier we used to "Runtime.exec()" qmail-inject
and manually give it the messages. This way, qmail would go on and do the
delivery. We would then parse the log files to find the status of the
message.
1.1 We had a unique "from"
address for each blast for each user to uniquely identify each email sent (in
maillog). Sometimes, instead of logging the "From" address, the maillog would
have the "replyto" address. Any ideas why? Is there anything else that can be
used to uniquely identify a message?
1.2 For each blast we want to
handle the bounced emails individually (we would need to update the appropriate
table). What do we do for that? We cannot just "set" environment variables since
there will be multiple mail-merges and blasts happening simultaneously.
1.3 Usually after about 5,000
deliveries, the messages would be stuck in the queue. We then added the CNAME
lookup patch, and this increased to about 10,000. Currently, we "prune" the
lists uploaded by the users and send messages in chunks of 2000, with less than
30 concurrent messages. Any suggestions what could be the culprit? What can we
do to circumvent this problem?
1.4 What would be the best
possible way to handle unsubscribe requests. Currently we invoke a java program
from the .qmail file that updates the database. Any suggestions how this can be
improved upon?
2. We then decided to switch over to using
qmail-remote, to circumvent the queue and the logging problem. This effectively
means we will have to do our own logging. Is there anyway to hand over different
messages to qmail-remote rather than invoking it for each message? We have now
decided to change the implementation so that at any point of time, there will be
as many threads sending messages as the qmail concurrency (say around 100), and
the messages themselves will be broken into chunks of 300 to 500 each. How can
we improve this?
3. Currently, we have our own implementation for
checking bad e-mail addresses, list management, handling bounces and mail-merge.
Are there any guidelines/sample code available (any language), that we can look
at?
4 . What other things should we keep in mind to
provide stability to the system? What patches to qmail are advisable to be
installed? What should be the typical server configuration for such a system?
5. On a parallel note, what would be the best
algorithm to track forwarded messages? We make use of cookies right now (but
that provides 50% accuracy).
I apologize if I broke some protocol and asked some
questions that do not pertain to this list.
Regards,
manav. |
