tlsv1 alert unknown ca: SSL alert number 48

[Joseph Tam]

> Jan 28 22:42:44 dovecot: imap-login: Disconnected (no auth attempts in 0
> secs): user=<>, rip=192.168.1.16, lip=192.168.1.3, TLS: SSL_read()
> failed: error:14094418:SSL routines:ssl3_read_bytes:tlsv1 alert unknown
> ca: SSL alert number 48, session=
> ...
> # SSL/TLS support: yes, no, required. <doc/wiki/SSL.txt>
> ssl = yes
> ssl_cert = </etc/ssl/certs/dovecot.pem
> ssl_key = </etc/ssl/private/dovecot.pem
> ssl_ca = </etc/ssl/private/cert.pem

Are you using client verification (i.e. mutual authentication of mail
client and server)?

If not, just comment out ssl_ca.

Joseph Tam <jtam.home at gmail.com>