Re: Sendmail or Qmail ? ..
On Thu, 2003-09-04 at 04:58, Eric Sproul wrote:
> On Thu, 2003-09-04 at 01:43, Rudi Starcevic wrote:
> > Hi,
> > Sorry to bother you all with this repeat question.
> > I've have searched around and seen plenty of opinions but I'd like to
> > ask again and get the latest from this list.
> > Sendmail or Qmail ? That is my question.
> I work at an ISP that used to use Qmail, but now uses Sendmail. There
> are several reasons why the switch was made, none having anything to do
> with the "religion" surrounding either one. The following is my
> opinion, illustrated with some examples from my company.
> First, scale is a consideration. Once we began to grow our customer
> base, our email volume began to increase dramatically. Qmail queues
> everything to disk, so the more mail you do, the more pressure you put
> on your disk I/O. The server running Qmail was always blocking while it
> tried to keep up with the disk writes. We had to decide whether to
> spend huge $$$ on a big-iron server to handle it all, or to go cheap and
> modular using some other MTA. We opted for the latter. We replaced our
> single mailserver with four mail routing servers and two mail storage
> servers, where customer accounts reside.
qmail is more modular than any other MTA, especially Sendmail.
> Sendmail uses RAM more heavily than Qmail, relieving some of the disk
> I/O pressure, and improving performance under heavy loads. In order to
> go modular, we needed a directory service to tie it all together (so
> that each mail router can reference a system-wide config, and figure out
> where the mailbox is). We chose OpenLDAP. At the time (1999), Qmail
> did not have LDAP support (correct me if I'm wrong). Sendmail did.
> Even if Qmail did have LDAP support then, Sendmail's source was *much*
> easier to dig through for the performance tuning we did.
> Sendmail's milter plug-in system has also been invaluable when we
> implemented server-side bayesian spam filtering, and as we work on virus
qmail being modular has the capability of performing this also.
> Today we are very happy with our Sendmail installation. Debian and
> Sendmail play very happily together, and with our modular setup we
> process over 4 million messages a day with over 60,000 mailboxes. Yes,
> Sendmail has had several high-profile vulnerabilities, but with Debian
> and apt, we were able to stay on top of it with little difficulty. I
> can see how Qmail could look attractive to a smaller site with a less
> complex setup, but for us, Sendmail was the way to go.
Good to know you are happy. That makes a big difference.