Sending mails using postfix to gmail account

I have a problem with using postfix for sending mails to my gmail account.
Here is the error that I get in /var/log/mail.log
Feb 3 17:15:01 RISH postfix/pickup[14115]: 703D9162871: uid=33 from=
Feb 3 17:15:01 RISH postfix/cleanup[14133]: 703D9162871:
Feb 3 17:15:01 RISH postfix/qmgr[14116]: 703D9162871:, size=3183, nrcpt=1 (queue active)
Feb 3 17:15:01 RISH postfix/error[14122]: 703D9162871:, relay=none, delay=0.14, delays=0.09/0/0/0.05, dsn=4.3.0, status=deferred (unknown mail transport error)


hostname -f

cat /etc/hosts    localhost    RISH master slave
# The following lines are desirable for IPv6 capable hosts
::1     ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters

I need to send a mail from the localhost to my gmail account. Could someone please help me with this…


What is the output of the command “postconf -n”?