So some spam signups just happened (all username12345678@gmail.com format e-mail) This caused bounced mail to increase, causing Mailgun to block our domain to prevent it getting blacklisted.
So:
- Mail temporarily doesn’t work
- I closed signups for now
- I will ban the spam accounts
- I will check how to prevent (maybe approval required again?)
Stay tuned.
Edit: so apparently there is a captcha option which I now enabled. Let’s see if this prevents spam. Registrations open again.
Edit2 : Hmm Mailgun isn’t that fast in unblocking the domain. Closing signups again because validation mails aren’t sent
Edit 3: I convinced Mailgun to lift the block. Signups open again.
I’ve run into this issue with some of my servers in the past and it’s a real PITA to deal with because not only do you have to mitigate the issue, but then you have to make requests to get de-blacklisted, etc. I finally got sick of it all and installed a Barracuda spam firewall in front of the mail server. I have MUCH easier control over IMAP/SMTP now.