When building an email server we must always make sure we are not OPEN RELAYS. If you build a server that is an open relay you will soon discover that users not of you own are using your server to send an army of spam. You will also learn that your server is blacklisted, and depending on the damage and how long it has been compromised may need a new IP and Hostname, due to the original being on so many blacklists its not worth trying to get off all of them.

IPSWITCH has made an alternative to Microsoft popular Exchange server called Imail. The current version of Imail is version 11.

To secure the IMAIL server you must first get into the SMTP server settings.
1. From the Imail console Click Services –> Select Imail SMTP Server –> Configure Services

Configuring Relay settings in Imail server

2. Once you are in the Configuration options You will see Relay for. This is where you set the Relay type.

configuring Imail relay settings

Imail has 5 relay types, No Relay, Address, Local users, Local hosts, Anyone.

No Relay is what it says no relay, the server will not send mail for anyone.

Addresses setting will allow certain IP or whole IP subnet to send email from the server. E.g Your internal network is 192.168.2.0, then you could set addresses and set that IP range, this will allow Imail to relay for any one on the 192.168.2.0 network.

Local Users – you can create local user accounts on the server but this is time consuming.

Local hosts – which will allow local hosts.

Anyone – this is a NONO this will allow anyone anywhere to relay mail from your server only use this for testing purposes.