I am the administrator on a G-Suite for Education domain.
We have a domain name set up (say ourschool.org) and students use username@ourschool.org to log in to their Google accounts.
Our MX records however are set up to facilitate an O365 account on the same domain. This O365 account is used by staff for e-mails and for students to get access to Microsoft Office for free at home. We don't want this to change.
Obviously we knew this when we set up the Google account – we had no requirement for mail use on the Google accounts.
However, we're now missing a few small features which the curriculum IT staff would like to access – feedback notifications (through e-mail), etc.
We've purchased another domain and set up the relevant Google MX records. We've also added this as an alias in our Google account. Let's call it our.school.
Is there any way to force all e-mails (especially the feedback notification e-mails etc) to use this aliased domain our.school whilst still allowing staff/students to login using their existing e-mail addresses on the original ourschool.org domain?
Best Answer
I'd like to elaborate from my comment above. I would look into using some of the incoming routing options available through the admin console.
Split Delivery
This is where you can deliver to either G Suite or your O365 depending on rules provided.
Dual Delivery
Messages are delivered to both G Suite and O365. I have used this option in the past but with an on-prem exchange server. It worked really well because, in my opinion, Gmail has some of the best spam filters out there and we took advantage of the spam filtering before it was delivered to exchange. Also if Exchange went down we had a backup of external emails.
Have a good read through this G Suite Support Article on Email Routing and Delivery. It'll step you through your setup in the admin console.
Word of Caution
Because you are using an intermediary, you may run into problems with SPF checking. Some mail servers may not like what you are doing and drop the emails. I would look into this question from Server Fault, or this one for some guidance.