I have a script that I use to set things up;
Code:
#!/bin/bash
# should be run as user zimbra
# su - zimbra
# change ServerName if run on a different zimbra server.
ServerName="My Server"
# list current settings
zmprov gas -v | grep MyNetwork
# make the change
# 123.123.123.123/32 use all IP addr bits for machine 123.123.123.123
# you can change the /32 to have an entire subnet if needed
# but be cautious as if a firewall is on the front end you may become
# an open relay
zmprov modifyserver $ServerName zimbraMtaMyNetworks '127.0.0.0/8
123.123.123.123/32'
# Confirm change
zmprov gas -v | grep MyNetwork
If you can get to the Admin web page then you can also set it there under "Configuration" "Servers"