Upgraded my server to 20.04. Now I can’t get IMAP working through dovecut. I get:
Aug 1 23:25:53 defaria dovecot: imap-login: Error: Failed to initialize SSL server context: Can’t load SSL certificate: error:140AB18F:SSL routines:SSL_CTX_use_certificate:ee key too small: user=<>, rip=188.8.131.52, lip=184.108.40.206, session=<iKgXGN+rCIC4tj+F>
I found many solutions to this problem but none seem to work. I’ve generated and re-generated server keys, signing certificates, and the like and configured dovecot to look at them yet all I get is this cryptic error message. I had this all configured nicely before and just updating from 18.04 -> 20.04 broke this.
How can I fix this? Step by step… How to I supposed generate a cert and a key and properly configure them into dovecot so that imap works again?
Funny thing is I can drive a session through telnet to imap and I can log in an access messages. But when I try to do the same with my mail client (thunderbird) I get the above error written to /var/log/mail.log