Disk IO is much more important for raw email processing than processor
speed or RAM. Count of mailboxes isn't a great way to determine how
busy the system will be since 20k boxes that are lightly used will
create less load than 50 very active mail boxes that have >100 GB of
storage. How will your users access their email, POP3, IMAP4, web
mail? Are you going to relay out bound email for these users as well?
How about SSL/TLS secured SMTP, POP, IMAP, and HTTP? Any consideration
for AV and anti-spam and if so will those be run on the same server?
How important is redundancy?
On 5/4/2011 12:23 PM, Shepherd Nhongo wrote: >
> On Wed, May 4, 2011 at 5:12 PM, Kulkarni Shantanu
> <firstname.lastname@example.org <mailto:email@example.com>>
> * Ozgur Ozdemircili <firstname.lastname@example.org
> <mailto:email@example.com>> [110504 20:30]:
> > Hi,
> > A quick question for the wexperienced ones over here. Can you
> please share
> > your hardware configs and users/ domains you have on them?
> > I am building a qmail server for 20000 accounts and the machine is:
> > AMD Bi Opteron 612816x 2.00+ GHz 2x12 MB L3 - QPI 2x6.4 GT/sec
> > 32 GB DDR3
> > 2x 1500 GB - SATA2
> > How many users / domain can I host in the machine with efficency?
> qmail-ldap patch should be the best option to run 20000 user mail boxes.
> As for hardware 32GB ram is an overkill :-) 3TB HDD is still fine but
> how will you backup your mail server?
> Ever heard of virtualisation? I have four blade servers in different
> parts of the world running Virtual Machines that have qmail mta. I
> have written a small backup script that relies on cron and run every
> 11hours of the day.It's working well for me but then my capacity is
> not anywhere closer to 20000 i have just checked and the total is
> 12034 mailboxes with about 200GB of files.Most of my users are using
> imap and some bleed all the emails using their mail delivery agents.
> qmail takes up very less resources. If you have av scanners or spam
> handlers; they will take more resources.
> On one particular machine Intel Xeon 1.86GHz, with 2Gb RAM we are
> handling around 5000 live (working )email addresses. The same machine
> does av scanning and also has webmail (so apache too). The machine has
> uptime of 354 days (up since we got it) with load average 0.18 and
> maximum load so far 18.2.
> www.shantanukulkarni.org <http://www.shantanukulkarni.org>
> Shepherd Nhongo
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