Filter Check

filter-check notifies us if email sent via our servers is landing in the spam box of the three major providers - Google, Microsoft or Yahoo.

We have created email accounts on all three providers. filter-check iterates over all of our relay IP addresses and over all three providers to send an email from each IP address to each provider. Then, it waits a bit and tries to check for that message via IMAP. If the messages is in the Spam box or doesn’t arrive at all, it raises an alert.

filter-check is run via pigeon. Pigeon manages the timing and takes care of iterating over all the available postfix instances (this check is run on each of our mailrelay servers).

If we get an alert, follow these instructions.