I've pasted my full main.cf and master.cf to Pastebin. I checked the config variables $smtpd_*_restrictions of the running postfix process with postconf, and they are as written in main.cf.Ĭan anyone suggest what I need to do to get past this error? Smtpd_relay_restrictions = permit_mynetworks,permit_sasl_authenticated,reject_unauth_destinationīut trying to send an email by SASL authentication with Thunderbird from my workplace through it (the outgoing server) still gives me SMTP session failed: 554 5.7.1 : Relay access denied Smtpd_client_restrictions = $mua_client_restrictions Mua_client_restrictions = permit_mynetworks,permit_sasl_authenticated,reject As you see from the error logs, the email is sent via rootatdevdotdigiklugdotcom which is not a Zoho Mail address. Following other similar Q&As on this forum, I prepended $smtpd_restrictions with permit_mynetworks and added my company's IP address to $mynetworks. Restart the mail server by issuing the following command: service sendmail restart Step 5: Send test email echo 'Test 1 from $(hostname -f)'|mail -s 'Test 1 $(hostname -f)' ConclusionĬongratulations, you have now installed SMTP relay / smarthost for your sendmail mail server.I'm trying to set up a postfix 3.6.2-1 server on CentOS 7 that I don't have physical access to (have sudo, but upgrading everything is not an option) and needs client & relay clearance from my workplace. Rebuild the configuration file with the following command: /etc/mail/make Step 4: Restart the mail server

Replace it with the following line define(`SMART_HOST', `')dnlĭefine(`RELAY_MAILER_ARGS', `TCP $h 587')dnl Step 3: Regenerate configuration file Step 2: Configure the MTAĮdit /etc/mail/sendmail.mc and find the following line dnl define(`SMART_HOST', `')dnl Please read this article for instructions if you don’t know how to connect. What is the easiest and fastest way to configure this My external SMTP server uses authentification.

I have no intrest in sending 'local mails' to root or any other user. You must be logged in via SSH as sudo or root user. From CentOS 7, I want to send emails from to or, etc. This tutorial assumes that you are logged in as a sudo user. encrypt headersizelimit 4096000 relayhost :587.

You must be logged in via SSH as sudo or root user. Setup SendGrid as a Postfix relay host for better deliverability and advanced.

A Cloud VPS or Dedicated Server where sendmail is installed.

If you want or need to set up your mail server to send all outgoing mail to a specific server that will handle the delivery to the recipients you can use this article to set up your SMTP relay / Smarthost with Sendmail.

Smtp relay centos 7