Shami's Blog

Sysadmin, Because Even Developers Need Heroes

Adding 'on behalf of' To Outgoing Emails With Postfix

2016-04-28 by Mohammad H. Al-Shami

I used to be a big fan of Mandrill. I used to use it as an email gateway for my personal servers. It’s easy to use and it’s cheap (Or free if you send less than 12,000 emails per month). I liked not having to setup SPF, DKIM, and DMARC for my small setups. Even for smaller clients I wouldn’t bother with that and just use Mandrill. Emails just show up with the following sender [email protected]; on behalf of; [email protected]


Randomize Source IP Addresses With Postfix

2016-04-27 by Mohammad H. Al-Shami

Sometimes when you have a high number of outgoing messages services like Yahoo! and Gmail might block you. To prevent that you need to distribute your outgoing emails through a set of IPs. I used HAProxy for that along with a number of FreeBSD Jails. That solution is a bit tedious, even though after I started using Salt things became a bit easier it was still too complicated for my taste.


Throttling Outgoing Emails To Certain Domains With Postfix

2009-03-29 by Mohammad H. Al-Shami

I’ve been busy setting up a PHPlist server for my employer. All tests went ok, but as soon as we sent our first newsletter Yahoo! blocked the server. After looking around for a solution people suggested we sign all outgoing emails with DomainKeys and not hammer Yahoo’s servers with consecutive connection.