==== Required information ====
- iRedMail version: v0.2.1 (LDAP)
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): LDAP
- Linux/BSD distribution name and version: FreeBSD / jail
- Related log if you're reporting an issue:

connect from fqdn[a.b.c.d]
setting up TLS connection from fqdn[a.b.c.d]
.
<other logs, another connections,  few seconds>
.
warning: network_biopair_interop: error reading 5 bytes from the network: Connection reset by peer
SSL_accept error from fqdn[a.b.c.d]: -1
lost connection after STARTTLS from fqdn[a.b.c.d]
disconnect from fqdn[a.b.c.d]

====

Hello

I have a strange issue with postfix, found plenty of similar issues on the net, but with no working fix.
The trouble is, that some mails pass and some do not.
For example daily/monthly/weekly reports from my servers are not delivered at all.
I thought that there was a problem with my CAcert cert so I generated new cert using the provided script
(tools/generate_ssl_key) but it didn't help.

config:
smtpd_tls_security_level = may
smtpd_tls_loglevel = 1
smtpd_tls_key_file = /etc/ssl/private/iRedMail.key
smtpd_tls_cert_file = /etc/ssl/certs/iRedMail_CA.pem
smtpd_tls_CAfile = /etc/ssl/certs/iRedMail_CA.pem
tls_random_source = dev:/dev/urandom

on the sending mail server side the delivery look ok at the beginning:
Message accepted for delivery
At the same time as the error on the receiving side appears, in the sender it looks like:

STARTTLS=client, error: connect failed=-1, reason=unknown, SSL_error=5, errno=60, retry=-1
ruleset=tls_server, arg1=SOFTWARE, relay=fqdn, reject=403 4.7.0 TLS handshake failed.