Read more about this in our support site Zimbra Domain Alias
Q: For Zimbra how do I add a domain alias so user@domain1.com also receives mail for user@domain2.com?
A: Two things are needed:
1) Make sure your DNS's MX record for domain1.com and domain2.com point to the appropriate mail server (consult with Smedia if your not sure how to do this by creating a support ticket, or calling 414.755.2999)
2) Submit the form below: