Mailbaby for Zimbra

MailBaby for Zimbra 8.8.x Configuration

To relay outgoing mail through MailBaby using Zimbra 8.8.x, follow these steps:

1. Update Your SPF Record

For each registered domain, update the SPF record to authorize your Zimbra server and MailBaby:

v=spf1 ip4: include:spf-c.mailbaby.net -all

Replace with the public IP address of your mail server for origin ip verification.

2. Configure Relay Authentication

Log in as the Zimbra user usually zumbra

Create the relay password file with your MailBaby credentials:

echo "relay.mailbaby.net user:password" > /opt/zimbra/conf/relay_password

Replace user:password with your MailBaby relay credentials.

3. Build the Password Map

postmap /opt/zimbra/conf/relay_password

Check that the map was created successfully:

postmap -q relay.mailbaby.net /opt/zimbra/conf/relay_password

If correct, it will return the configured username.

4. Apply Zimbra MTA Settings

Run the following commands, replacing with your Zimbra mail server’s fully qualified domain name:


zmprov ms zimbraMtaSmtpSaslPasswordMaps lmdb:/opt/zimbra/conf/relay_password
zmprov ms zimbraMtaSmtpSaslAuthEnable yes
zmprov ms zimbraMtaSmtpCnameOverridesServername no
zmprov ms zimbraMtaSmtpSaslSecurityOptions noanonymous

5. Postfix Configuration

Update Postfix to use the relay password map:

postconf -e smtp_sasl_password_maps=hash:/opt/zimbra/conf/relay_password

Set MailBaby as the relay host:

zmprov ms zimbraMtaRelayHost relay.mailbaby.net:587

6. Restart Zimbra MTA

Finally, restart the MTA service to apply changes:

zmmtactl restart

✅ At this point, Zimbra should relay outgoing messages through MailBaby. Be sure to test sending an email and check your mail logs for any authentication or relay errors. Please review mailbaby best practices.