Configuring MailSite as secondary backup server How to configure MailSite as secondary backup server This document assumes that there is a working mail server and DNS server with the appropriate MX Record in place. The purpose of a secondary mail server is to store messages for the primary mail server when it's offline or unavailable. It is not intended to have end-users retrieve or send messages, only to store inbound message until the primary server is available. A secondary will automatically re-attempt delivery to the primary mail server at regular intervals, usually over a five day period (54 attempts) before returning the message to the sender.

CONFIGURATION
After installing a new mail server to be used as a secondary backup, the server should be configured to act as a backup for certain domains only, thus preventing abuse of the service. The secondary mail server should be configured to 'Accept mail for relay TO these domains' by adding the internet domains (mydomain.com) that you wish to perform backup for. Information on how to do this within MailSite can be found in Knowledge Base document 10001, by following the link below

Add an additional MX Record to the DNS server for the secondary server. This has to be a lower priority than the primary mail server. Typically MX=10 for the primary, and MX=20 for the secondary (backup) mail server.

DNS EXAMPLES
In this example we assume your primary internet domain name is: mydomain.com Your existing (primary)

mail server name is: mail.mydomain.com

And has the existing MX Record:
mydomain.com MX (Mail Exchanger) Priority: 10 mail.mydomain.com mail.mydomain.com A (Address) 10.0.0.100 ß(whatever the IP address is)

Your new (secondary) mail server is: backup.mydomain.com Add an additional MX Record to the DNS similar to the following:

mydomain.com MX (Mail Exchanger) Priority: 20 backup.mydomain.com backup.mydomain.com A (Address) 10.0.0.200 ß (whatever the IP address is)

Now, whenever the primary mail server is offline or because unavailable for any reason, messages from the internet will not bounce back to the sender, but will be delivered to the backup mail server. The backup mail server will re-attempt deliver to the primary mail server typically for 54 tries (which is about four and a half days). If the backup isn't able to deliver to the primary mail server after time, the backup mail server will bounce any messages back to the sender as "undeliverable".

CONFIGURING MAILSITE MANUALLY
You can use the routes feature of Mailsite to manually forward mail for particular domains. To manually set up the routes, follow the steps below:

1. Open the Mailsite console.
2. Click on "Server"
3. Double click on "Routes"
4. Enter the name of the new route and select force, additional or default.
5. Click "Add"
6. Next click on the "Routes" button.
7. Add the hosts or IP addresses of the intended mail servers domains then click add.
8. Click OK