Migration advice

%3CLINGO-SUB%20id%3D%22lingo-sub-2301174%22%20slang%3D%22en-US%22%3EMigration%20advice%3C%2FLINGO-SUB%3E%3CLINGO-BODY%20id%3D%22lingo-body-2301174%22%20slang%3D%22en-US%22%3E%3CP%3EHi%20all.%3C%2FP%3E%3CP%3E%26nbsp%3B%3C%2FP%3E%3CP%3EHope%20everyone%20is%20well.%20I%20was%20looking%20for%20some%20advice.%20We%20are%20in%20the%20process%20of%20a%20merger%20and%20we%20are%20getting%20new%20Office%20365%20accounts%20in%20the%20acquiring%20company%E2%80%99s%20Office%20365%20tenant.%3C%2FP%3E%3CP%3EI%20wanted%20some%20advice%20with%20regards%20to%20on-premises%20mail%20flow.%3C%2FP%3E%3CP%3EHere%20is%20my%20setup%3A%3C%2FP%3E%3CP%3EMy%20AD%20domain%20is%20mycompany.local.%3C%2FP%3E%3CP%3EExchange%20is%202016%20hybrid.%20All%20email%20is%20in%20Exchange%20Online%20within%20my%20current%20tenant.%3C%2FP%3E%3CP%3EI%20am%20hosting%206%20companies%20with%20vanity%20domain%20names%20for%20each%20of%20them.%3C%2FP%3E%3CP%3EMX%20for%20each%20company%20points%20to%20EXO%20and%20all%20email%2C%20even%20from%20on-premises%20gets%20sent%20out%20via%20EXO.%3C%2FP%3E%3CP%3E4%20of%20the%206%20companies%20I%20am%20hosting%20will%20move%20across%20to%20the%20new%20the%20tenant.%3C%2FP%3E%3CP%3EThe%20domains%20will%20be%20removed%20from%20my%20tenant%20and%20added%20to%20the%20new%20tenant.%3C%2FP%3E%3CP%3EThe%20problem%20I%20am%20facing%20is%20that%20I%20have%20a%20lot%20of%20on-premises%20systems%20that%20sends%20email%20to%20my%20mailboxes%20hosted%20in%20EXO.%3C%2FP%3E%3CP%3EEach%20of%20my%20users%20have%20a%20remote%20routing%20address%20of%3A%3C%2FP%3E%3CP%3E%3CA%20href%3D%22mailto%3AUser%40mytenant.mail.onmicrsoft.com%22%20target%3D%22_blank%22%20rel%3D%22nofollow%20noopener%20noreferrer%22%3EUser%40mytenant.mail.onmicrsoft.com%3C%2FA%3E%3C%2FP%3E%3CP%3EWhat%20is%20the%20best%20way%20to%20ensure%20mail%20flow%20from%20on-premises%20still%20flows%20to%20my%20users%20that%20will%20be%20hosted%20in%20the%20new%20tenant%20while%20still%20being%20in%20a%20supported%20scenario%20with%20Microsoft%3F%3C%2FP%3E%3C%2FLINGO-BODY%3E%3CLINGO-LABS%20id%3D%22lingo-labs-2301174%22%20slang%3D%22en-US%22%3E%3CLINGO-LABEL%3E2016%3C%2FLINGO-LABEL%3E%3CLINGO-LABEL%3EExchange%20Online%3C%2FLINGO-LABEL%3E%3CLINGO-LABEL%3EExchange%20Server%3C%2FLINGO-LABEL%3E%3CLINGO-LABEL%3EHybrid%3C%2FLINGO-LABEL%3E%3CLINGO-LABEL%3EOffice%20365%3C%2FLINGO-LABEL%3E%3C%2FLINGO-LABS%3E
Regular Contributor

Hi all.

 

Hope everyone is well. I was looking for some advice. We are in the process of a merger and we are getting new Office 365 accounts in the acquiring company’s Office 365 tenant.

I wanted some advice with regards to on-premises mail flow.

Here is my setup:

My AD domain is mycompany.local.

Exchange is 2016 hybrid. All email is in Exchange Online within my current tenant.

I am hosting 6 companies with vanity domain names for each of them.

MX for each company points to EXO and all email, even from on-premises gets sent out via EXO.

4 of the 6 companies I am hosting will move across to the new the tenant.

The domains will be removed from my tenant and added to the new tenant.

The problem I am facing is that I have a lot of on-premises systems that sends email to my mailboxes hosted in EXO.

Each of my users have a remote routing address of:

User@mytenant.mail.onmicrsoft.com

What is the best way to ensure mail flow from on-premises still flows to my users that will be hosted in the new tenant while still being in a supported scenario with Microsoft?

0 Replies