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We have new server configured, the problem is the ISP.
They not allow port 25 for sending mail.
Fortunately we have another existing postfix server .
After edit main.cf in new server, we can send email through existing server.
The only change to do is :
Edit main.cf, find relayhost line and add existing server hostname
relayhost = mail.rasyid.net
save and restart postfix.
To make sure it works you can see maillog and mailq .