How do I configure the appliance to allow Drupal to relay email via an internal Exchange server?
To configure postfix to relay mail to another mail server (e.g., Exchange), set the value for "relayhost" in /etc/postfix/main.cf like this:
sed -i '/relayhost/ s/=.*/= [my.exchangeserver.net]/' /etc/postfix/main.cf
Unfortunately, there doesn't seem to be an easy way of doing this from the webmin interface.
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