I ran into two issues when setting up Let’s Encrypt SSL certificates on two of my servers - permission issues for Exim and the certbot cron job supplied by the package doesn’t handle the renew very well for nginx, exim or dovecot. Resolving Exim’s Permission Problems 1. Create a new group. I named it sslcerts. Add the exim user to that group. If you’re not using Debian, adjust the user in the command below.
I’ve read a number of articles over the past few days about the possible Android botnet and Yahoo! mail. No consensus yet but that’s not necessary to stop the spam at the server level, at least in my case. Of the spam I received so far, these characteristics stand out: Only one of my mail accounts is receiving the spam. It’s not an account that usually receives spam. My long-time mail addresses that seem to have made it to most of the spam lists don’t get this spam.