MailerQ 4.3.0 released

MailerQ 4.3.0 is out. This version contains only a couple of small changes compared to our previous 4.2.10 release. However, because some config file settings now have a different meaning, we decided to up the version number to 4.3.

Breaking changes

The smtp-defaultips and smtp-defaultip config file variables are deprecated. We therefore recommend to no longer use them. You can use the following variables instead:

• smtp-default-ips
• smtp-mappable-ips
• smtp-unmappable-ips

The smtp-default-ips variable holds the default IP addresses (comma or semicolon separated) for sending outgoing emails. These IP's are used if the per-message JSON does not explicitly have an "ips" property. If no IP's are set in the config file either, the first available IP address on your server that is covered by your license is used to send out the message.

The old smtp-defaultip and smtp-defaultips variables have become aliases for this new smtp-default-ips setting. Watch out: the procedure for choosing the outgoing IP address is different than before. If no IP address was set in the JSON, MailerQ used to try to send out the mailing from every possible IP (possibly iterating over thousands of addresses). Now it only tries the default IP's listed in the config file.

Emails injected over SMTP used to be sent out from the same IP addresses as to which they were injected. We have however now added the config variables smtp-mappable-ips and smtp-unmappable-ips to give you control over this. Now only mails received on a mappable IP address are sent out from that same IP. Messages received on unmappable IP's use the addresses set in the smtp-default-ips variable.

Both the smtp-mappable-ips and the smtp-unmappable-ips settings hold comma separated lists of IP ranges. The default value for the mappable IP's is "0.0.0.1/0", meaning: all your IP addresses are mappable. The default unmappable value is "127.0.0.0/8,192.168.0.0/16". The combination of these two settings have the effect that all your IP addresses are mappable, except for the local IP addresses. If you submit a message to a local IP or to localhost (127.0.0.1), it will be sent out from the default IP's, otherwise from the public IP.

When a messages comes in over SMTP, MailerQ now compares the incoming IP with the ranges set in smtp-mappable-ips and smtp-unmappable-ips. If the IP address matches the first setting and does not match the second, MailerQ considers the IP address to be mappable. The mail will then also be forwarded from that same IP address. If the address was not mappable, it will be sent out from the IP's set in smtp-default-ips.

Other changes

We have also changed the default config file that comes with a MailerQ installation. The initial config file that is copied to the /etc/mailerq directory when someone installs MailerQ for the very first time now has better defaults. A first time user can leave most of the initial settings intact because we have optimized it get MailerQ running with a minimum of dependencies.

There was a small issue in loading the openssl library. On some Ubuntu systems, the latest openssl 1.1 library is stored on the system as libssl.so.1.0 (and not as libssl.so.1.1 as you would expect). Although this is strange, MailerQ now has a workaround to handle this situation.