Configure Trusted Networks and Hosts

An XCCDF Group

Description

Edit /etc/postfix/main.cf, and configure the contents of the mynetworks variable in one of the following ways:

If any system in the subnet containing the MTA may be trusted to relay messages, add or correct the following line:
```
mynetworks_style = subnet
```
This is also the default setting, and is in effect if all my_networks_style directives are commented.
If only the MTA host itself is trusted to relay messages, add or correct the following line:
```
mynetworks_style = host
```
If the set of systems which can relay is more complicated, manually specify an entry for each netblock or IP address which is trusted to relay by setting the mynetworks variable directly:
```
mynetworks = 10.0.0.0/16, 192.168.1.0/24, 127.0.0.1
```