Speed up exim

[droidman]

Hi, i run a medium size vps and i'm currently only using it to mail our clients, the website is hosted at another server, we have arround 100.000 members and every time i try to mail them thru the vps it cannot send more than 1 or 2 mails per second, it is very slow sometimes takes more than 2 days to send a newsletter.
I also installed nginx and saw a big diference on the http performance, is it possible to make some small changes to speed up exim for mail purposes or is this strictly related to hardware ?

[cPanelTristan]

I believe that the hardware limitations are the likely cause for the speed for message delivery. You could always get another machine just for email delivery to see if only processing emails on the new machine would help with the performance of message delivery.

I did find the following article on speeding up exim processing, which would require being able to configure a RAM disk for exim for the message queues:

How to make Exim run a lot Faster - Computer Tyme Support Wiki

[droidman]

hi mate thank you for your relpy.
in fact it would probably be a good idea to get another server and when i make my e-mail sending exim redirects some of the traffic to the other server. i dont know how to do this or if it will increase the probability of the e-mail being flagged as spam.

[cPanelTristan]

The email isn't more likely to be flagged as spam provided it is sending from the correct IP and not spoofing the IP. Additionally, you can always ensure to setup SPF and domainkey records for the domains with the SPF record having the IP of the server sending the emails out to authenticate that server as the right one for emails. Provided you have it setup properly, using another machine to send emails won't increase the likelihood to be flagged as spam.

[droidman]

so it is possible to do this with another vps and cpanel ? do you know a good tutorial?

[cPanelTristan]

It is possible to do it with another VPS, but I don't know of a tutorial. Here are the steps that come to mind:

1. On the second VPS serving as the mail server, create the same email account(s) as email only accounts
2. Change the MX records for the domain(s) to point to the second VPS (mail) machine as the primary MX. Set a secondary MX to go to the first VPS (web server) machine.
3. On the first VPS serving as the web server, set the domains as "Backup Mail Exchanger" so that emails that fail going to the email server at any point (primary MX) will go into queue on the web server (secondary MX) and be held there until they can deliver to the mail server.

[droidman]

thank you!

By the way, isnt it possible to send e-mails also from the first vps, or to speed up i need at least to send from the first one that acts as a http server and more 2 or 3 vps servers that make the e-mail destribution ?
if i understand correctly, this will probably increase the e-mail delivery to servers like hotmail.com and others that block when sending bulk campaigns without those very expensive return path certifications

[cPanelTristan]

The emails won't be sending from the web server. The users will log into the email server for email not the web server for email and send from that server. As such, emails won't be sending from the web server at all unless the primary MX email machine fails and the emails then queue to the secondary MX (unless you are going to put the secondary MX onto yet another VPS and then instead it would queue there).

You are going to speed up exim delivery if you are only running a machine running exim and have taken offline MySQL, Apache and any other services that aren't necessary to the functioning of exim.