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Hi MS,
I am in the planing phase of doing 10 users Pilot Hybrid migration to office 365 in E3 plan using our Volume licence.
We have two 2016 exchange servers running in DAG
We also have email filtering done via Mimecast and for purpose of this exercise i want to leave email filtering to mimecast and not use EOP.
I want to get a clear idea of exact steps I need to take to configure this.
However, before I do anything i want to make sure it does't affect our SMTP or any other users from reading tons of articles and some previous experience with office 365 this are the steps i think needs to be performed.
- check prereq - all good
My questions Questions are
On step 14
If i add this TXT record this will not affect any mail flow this is purely for domain verification?
Question 2
on the step 15 -29 here
will that affect any existing mail flow or existing connectors as we have few there
Question 3
overall understanding is mailflow will still be going through exsting exchange server and other 240 users will not be affected and not other server or services such as smtp, scanning service will be affected due to this.
We never need to change MX records and we don't have to make any changes to mimecast?
Please clarify these ASAP, would be really appreciated.
Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
Hi Roy,
Thanks for your explanation.
The answer is yes. You can delete them from the DAG. About deleting anything, we need to confirm it again and again. Because some steps are not reverted. Your understanding is highly appreciated.
Best Regards,
Erick
Hi Erick,
Yes, i think we are getting confused.
Hybrid is only for now, we will be doing full migration to cloud so no on prem server will exist once we migrated all 350 users.
I understand we still need to have one on-prem exchange just for directory sync but no mailboxes will be on the local server.
So my question is I want to delete those 40 mailboxes which are already been migrated to office365. I used different batch files to migrated them so 40 users are all from different batches.
I want to deleted only those 40 users for now from local on-prem 2016 exchange so we don't have a local copy of those mailboxes on our local DAG storage .
Does that makes it more clear?
Hi Roy,
Since you use the Hybrid remote migration, the mailboxes are migrated to cloud when they are finished and there are only mailuses on your on-premise Exchange servers. Do you want to delete them under the mailboxes page in the EAC? If so, we don’t recommend you do it. If not, please let me know where you want to delete. To avoid any misunderstanding, it is very important for us and you to check it.
May I know whether you use the same batch to migrate these 40 users and other 350 users?
Best Regards,
Erick
Hi Erick,
I am referring to those 40 users who are already successfully migrated to office 365.
Can I delete their mailboxes on the local on-prem exchange server mailboxes now? As we need to start making some space on the storage.
Moving forward, once all 350 users have migrated to office 365, I will be removing the storage from the on-prem exchange server and leaving only bare minimum storage space attached.
Thanks
Regards
Roy
Hi Roy,
The answer is no. We don’t recommend users to do anything for the migration users if the migration has not completed. It may affect the migration users or batches.
Best Regards,
Erick