I have setup a postfix mail server to my local ubuntu system. it sends mail properly but for gmail account it is not received from gmail account.
here is the output of maillog
Jun 15 14:29:33 aum30 postfix/smtp[29509]: D2E95360910: to=, relay=gmail-smtp-in.l.google.com[74.125.24.26]:25, delay=3, delays=0.09/0/2.3/0.69, dsn=5.7.1, status=bounced (host gmail-smtp-in.l.google.com[74.125.24.26] said: 550-5.7.1 [117.223.148.98] The IP you're using to send mail is not authorized to 550-5.7.1 send email directly to our servers. Please use the SMTP relay at your 550-5.7.1 service provider instead. Learn more at 550 5.7.1 https://support.google.com/mail/?p=NotAuthorizedError g2si1886184plk.487 - gsmtp (in reply to end of DATA command))
How can I solve this?
Your ISP may provide SMTP relays which will accept mail from your IP, and these servers should be authorized to send mail.
Your IP 117.223.148.98 is on the PBL: https://www.spamhaus.org/pbl/query/PBL1528741