Greetings, I recently upgraded postfix and OpenSSL to 3.4.10 and 1.1.1d, respectively. These versions align with Debian GNU/Linux 10 (buster). Since the upgrade I've begun receiving regular log entries that look like this:
May 11 11:23:54 vasaconsulting postfix/smtpd[21870]: warning: TLS library problem: error:140E0197:SSL routines:SSL_shutdown:shutdown while in init:../ssl/ssl_lib.c:2086: These happen both when receiving and sending messages. Notably, when sending, the send will fail, but if I immediately resend, the message goes through. If instead I wait 10 or so seconds before resending, it will fail. When it occurs when receiving, the sending mailserver retries sometime later and seems to get through (though I haven't sought to verify repeated failures). I've seen this failure on both TLS v1.2 and v1.3 connections. Some messages seem to succeed as normal and expected but most fail due to this error and I haven't been able to identify a pattern. A survey of the mailing list suggests the problem as experienced by another user may have been related to tlsproxy but I have smtp_tls_connection_reuse set to no. Thanks and regards, Alexander Vasarab
