schmonz.com is a Fediverse instance that uses the ActivityPub protocol. In other words, users at this host can communicate with people that use software like Mastodon, Pleroma, Friendica, etc. all around the world.
This server runs the snac software and there is no automatic sign-up process.
OpenSMTPD 7.9.0p0 released https://undeadly.org/cgi?action=article;sid=20260916093956 #opensmtpd #openbsd #smtp #email #mail #freesoftware #libresoftware
Is it at all likely that any #SMTP call from *.bc.googleusercontent.com can be legitimate? I haven't seen any, only transparent spam/phish attempts, over the past six weeks of my logs.
I've blocked all 12 CIDR blocks ARIN lists for that service, under the assumption that no legitimate SMTP should come from there. If that's a mistake I suppose I'll find out eventually.
Running your own mail server with OpenBSD and OpenSMTPD - a great and complete blog post by @mboelen
https://bsd-audit.com/self-hosting/running-your-own-mailserver/