Jay,
That's the beauty of having multiple instances, not having to patch qmail.
All you need to do is install qmail once per machine (ie, /var/qmail1,
/var/qmail2,...). Then have the script that does the mailing call randomly
on of the /var/qmail#/bin/qmail-inject. This will emulate round robin
without any patching.
JES
Austad, Jay writes:
> Where would I start in the code to modify the QMQP servers list so that it
> would load balance between all of the servers in the list instead of just
> using the first one it can contact? This would be very useful to me. I
> assume qmail-qmqpc.c is one of them, are there others I would need to play
> around with?
>
> Jay
>
> -----Original Message-----
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]
> Sent: Friday, July 14, 2000 3:55 PM
> To: '[EMAIL PROTECTED]'
> Subject: Re: questions about performance and setup
>
>
> On Fri, Jul 14, 2000 at 02:29:06PM -0500, Austad, Jay wrote:
> > I already have Mandrake Linux 7.0 and 7.1 running on multiple Dell boxes
> > with no trouble, some of them took work to get going, but it runs well. I
> > have a few Crystal PC's here also that I may use instead, dual PIII 550's
> > with 512MB ram and 9 or 18GB 10000rpm drives. I'll probably use these for
> > testing.
>
> I agree with the earlier poster that more spindles for your queue
> (c/- raid) is a good thing in general.
>
> > The bulk of the messages will be the same content to many rcpt's.
> However,
> > once in awhile we'll have 100,000 different messages go out to 100,000
> > different people.
> >
> > Since the QMQP support under mini-qmail doesn't load balance, can I feed
> it
> > a hostname with multiple dns entries (round-robin dns)? Or better yet,
> how
> > easy would it be to modify the qmail code to just load balance between
> them?
>
> The manpage for qmail-qmqpc tells us that they have to be IP addresses
> in qmqpservers so a RR DNS won't help. If all of the messages are generated
> on one machine, then I'd be inclined to go for a much simpler solution
> than modifying qmail. I'd have an instance of qmail for each outbound
> server with the appropriate qmqpservers entry, then have your queue
> insertion script do a round-robin itself by simply cycling thru
> the qmail-inject command associated with each instance.
>
> for instance in 1 2 3 4 5
> do
> getnext_message_details()
> /var/qmail{$instance}/bin/qmail-inject currentmessage .... details
> done
>
> Or some such.
>
>
> Alternatively, if you have money to burn, maybe a layer four switch
> with load-balancing skills.
>
>
> Mark.
>
>
> >
> > Jay
> >
> >
> >
> > -----Original Message-----
> > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]
> > Sent: Friday, July 14, 2000 2:09 PM
> > To: '[EMAIL PROTECTED]'
> > Subject: Re: questions about performance and setup
> >
> >
> > > Here's what I need to know:
> > >
> > > 1. How well does qmail take advantage of multiple processors? How much
> >
> > Indreectly, quite well as it forks many processes, thus if the OS takes
> > good advantage of your CPUs, then qmail inherits that advantage.
> >
> > > memory and disk will I need? (we're at 50 million messages per month
> now,
> >
> > Are these message unique per target address or the same. If unique, your
> > requirements are vastly different and very queue/disk intensive. If they
> > are the same and you take advantage or VERP support on qmail, then
> > your load will mainly be sending related which will benefit from
> > more memory, multiple instances, etc.
> >
> > > and we only send out monday-friday, so that's over 2 million messages
> per
> > > day, and it's only going up)
> > >
> > > 2. How many messages per day would one estimate that each of these
> > servers
> > > could do?
> > >
> > > 3. I read about mini-qmail and how it's about 100 times faster blasting
> > out
> > > email to QMQP servers. Since you can specify multiple QMQP servers, if
> I
> > > have a fourth machine running mini-qmail and managing the actual mailing
> > > list, can I add the other 3 as QMQP servers and have it load balance
> > between
> > > all 3 for sending out mail? (this way I could add more servers easily
> if
> > I
> > > needed to)
> >
> > The qmqp support doesn't load balance. It simply takes the first one
> > it can connect to.
> >
> > > 4. Can I easily make qmail run an external script for each bounced mail?
> >
> > Absolutely.
> >
> > > 5. Anything else I should know?
> >
> > That all hinges on whether your emails are unique for each recipient or
> > not. Or more importantly, the average number of recipients per unique
> > email.
> >
> >
> > Regards.
>
