[root@localhost ~]# echo "Subject: sendmail test gmail" | sendmail
-v myuser@gmail.com myuser@gmail.com... Connecting to [127.0.0.1] via relay... 220 localhost.localdomain ESMTP Sendmail 8.13.8/8.13.8; Fri, 3 Jun 2016 16:56:01 -0300
>>> EHLO localhost.localdomain 250-localhost.localdomain Hello localhost.localdomain [127.0.0.1], pleased to meet you 250-ENHANCEDSTATUSCODES 250-PIPELINING 250-8BITMIME 250-SIZE 250-DSN 250-ETRN 250-DELIVERBY 250 HELP
>>> MAIL From:<root@localhost.localdomain> SIZE=29 250 2.1.0 <root@localhost.localdomain>... Sender ok
>>> RCPT To:<myuser@gmail.com>
>>> DATA 250 2.1.5 <myuser@gmail.com>... Recipient ok 354 Enter mail, end with "." on a line by itself
>>> . 250 2.0.0 u53Ju1vI022862 Message accepted for delivery myuser@gmail.com... Sent (u53Ju1vI022862 Message accepted for delivery) Closing connection to [127.0.0.1]
>>> QUIT 221 2.0.0 localhost.localdomain closing connection

Jun  3 16:56:01 localhost sendmail[22861]: u53Ju13j022861: from=root, size=29, class=0, nrcpts=1, msgid=<201606031956.u53Ju13j022861@localhost.localdomain>, relay=root@localhost
Jun  3 16:56:01 localhost sendmail[22862]: u53Ju1vI022862: from=<root@localhost.localdomain>, size=330, class=0, nrcpts=1, msgid=<201606031956.u53Ju13j022861@localhost.localdomain>, proto=ESMTP, daemon=MTA, relay=localhost.localdomain [127.0.0.1]
Jun  3 16:56:01 localhost sendmail[22861]: u53Ju13j022861: to=myuser@gmail.com, ctladdr=root (0/0), delay=00:00:00, xdelay=00:00:00, mailer=relay, pri=30029, relay=[127.0.0.1] [127.0.0.1], dsn=2.0.0, stat=Sent (u53Ju1vI022862 Message accepted for delivery)
Jun  3 16:56:03 localhost sendmail[22864]: STARTTLS=client, relay=gmail-smtp-in.l.google.com., version=TLSv1/SSLv3, verify=FAIL, cipher=AES128-SHA, bits=128/128
Jun  3 16:56:04 localhost sendmail[22864]: u53Ju1vI022862: to=<myuser@gmail.com>, ctladdr=<root@localhost.localdomain> (0/0), delay=00:00:03, xdelay=00:00:03, mailer=esmtp, pri=120330, relay=gmail-smtp-in.l.google.com. [64.233.186.27], dsn=2.0.0, stat=Sent (OK 1464983764 l40si4464056qtc.52 - gsmtp)