On Thu, Dec 24, 2020 at 01:16:58PM -0500, James B. Byrne wrote:

> I would like to understand exactly what these postfix log messages tell me
> about starttls, if anything:

Generally, just the non-verbose "smtpd_tls_loglevel = 1" loggins is
quite sufficient, and the higher log levels in most cases just makes it
harder to find what's important among all the low-level detail.

> Dec 24 13:09:32 mx32 postfix-p25/smtpd[25786]: SSL_accept:SSLv3/TLS write 
> session ticket
> 
> Dec 24 13:09:32 mx32 postfix-p25/smtpd[25786]:
>   Anonymous TLS connection established
>   from accounting-2.internal.harte-lyne.ca[192.168.216.88]:
>   TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits)
>   key-exchange ECDHE (P-256)
>   server-signature RSA-PSS (4096 bits)
>   server-digest SHA256

This TLS handshake was successful, and negotiate TLS 1.3, with all sorts
of parameter details you probably don't care about (but 2048-bit RSA is
probably good enough, and your 4096-bit RSA key is overkill that
needlessly burns CPU-cycles).

The client did not present a client certificate (this is quite normal).

-- 
    Viktor.

Reply via email to