I'm in the middle of an Exchange 2010 to hybrid Exchange Online migration and I think that I have a problem…
I'm alone with this and I'm getting the knowledge reading the Microsoft documentation. I have a doubt and I hope that anyone of you can help me.
Right now my incoming email flow is something like this:
Internet email (I.E Gmail, hotmail, etc) –> On Prem AntiSpam (ASSP) –> On Prem Exchange
Outgoing email flow:
On prem Exchange –> Internet –> Internet Email (gmal, hotmail, etc).
So, my main concern is: Is there any problem with having an antispam between internet (o365) and my exchange server? Will the HCW fail or will make my mailflow fail?
I can see on the Microsoft documentation that is better to not have anything between on prem Exchange and Online Exchange but I will like to hear from someone ho has encountered this problem.
I know that I can change my mailflow to ignore the antispam but I would like to keep that feature for the mailboxes that will stay on my on prem exchange.
Thanks for you help and sorry if I've misspelled something, I'm from Spain and english is not my mother tong!
Best Answer
I've never performed a migration in this scenario, but this is easy enough to test. Run the HCW on your Exchange 2010 server and see if it completes successfully. The worst thing that can happen is that it doesn't complete successfully. In that case, you'll need to make adjustments and run it again.
If the HCW completes successfully then create a test user and mailbox and migrate that to Office 365. Then test email between an on premises mailbox and the migrated mailbox. Then test email between the migrated mailbox and an external recipient.