What server for a mail server

[Wojciech Puchar]

>>
>> I have a project where I should set-up a mail server for approximately
>> 12000 users, 4000 virtual domains, 15000 messages per day, 700 MB
>> traffic per day.

200 mails*users/day is safe assumption. maybe 1-2 of them won't be spams
means about 2.5 million mails a day, assume 5 millions because there are 
hours of low and high load.

i would use jail for a virtual domain and users on those - in this jail, 
use nullfs to share /usr (and save memory), sendmail+procmail+spamassassin 
works fine.

it WILL survive this on average modern machine (but with 4 or more disks) 
without problems, unless spamassassin turned off.

if not - it will need possible a few machines. POSSIBLY on one, with 2-4 
cores and lots of RAM, and properly configured spamassassin.

having every domain as jail makes it easy.

it server can't cope with this, add second and move some of it's jail to 
other. moving jails between servers is very easy.

for mail reception i would recommend dovecot. it just works (TM), supports 
imap, pop3, imap/ssl, pop3/ssl.

for webmail (if needed) - sqwebmail. it it's based on php or other crap, 
just normal C program that runs quick. webpage look can be customized by 
editing HTMLs.


BTW - anyone knows faster antispam software than spamassassin, but still 
very good.

spamassassin is mostly perl so it's bulky and slow, but it's excellent in 
not removing true mails, while removing spam very well. of course 
sa-update&sa-compile is a must.

hope it helps. i don't have such a load but about 1500 users total, 
running on single CPU (P4) machine with 1GB RAM and 3 disks,doing other 
things in the same time, and it doesn't have a problems doing this.
with spamassassin and arcavir (polish anti-virus program)