root=postmaster
mailhub={mailserver}:587
AuthUser={username}
AuthPass={password}
UseTLS=TES
UseSTARTTLS=YES
hostname={hostname}
FromLineOverride=YES
DEBUG=YES

sSMTP[13572]: Cannot open {mailserver}:587

sSMTP[13119]: Creating SSL connection to host
sSMTP[13119]: 220 {mailserver} ESMTP Postfix
sSMTP[13119]: EHLO {hostname}
sSMTP[13119]: 250 DSN
sSMTP[13119]: STARTTLS
sSMTP[13119]: 220 2.0.0 Ready to start TLS
sSMTP[13119]: SSL connection using (null)
sSMTP[13119]: Cannot open {mailserver}:587

sSMTP[13572]: Unable to set TLS_CA_Dir="/etc/ssl/certs/"

sSMTP[12962]: Unable to set TLS_CA_FILE="/etc/ssl/certs/ca-certificates.crt"

postfix/submission/smtpd[7557]: warning: dict_nis_init: NIS domain name not set - NIS lookups disabled
postfix/submission/smtpd[7557]: connect from unknown[{ip}]
postfix/submission/smtpd[7557]: SSL_accept error from unknown[{ip}]: -1
postfix/submission/smtpd[7557]: warning: TLS library problem: error:140760FC:SSL routines:SSL23_GET_CLIENT_HELLO:unknown protocol:s23_srvr.c:649:
postfix/submission/smtpd[7557]: lost connection after STARTTLS from unknown[{ip}]
postfix/submission/smtpd[7557]: disconnect from unknown[{ip}]