Solved

MX Records

Posted on 2016-07-26
2
64 Views
Last Modified: 2016-08-19
Im currently doing a migration of several users to O365, Ive changed all the DNS records apart from the MX records, however cannot add users alias's until I complete the DNS record, which I dont want to do until we are ready to migrate.

Can I ignore the MX record warnings and then add the alias, then when ready to migrate change the MX records? From my understanding users who send to my users on O365 external to my account O365 will still use the MX records and the emails will goto the current MX record destination. Is that right? This means they can continue to send and recive emails on the old system until I flick the switch and change the MX records, then all the users and alias's are already setup.
0
Comment
Question by:tonelm54
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
2 Comments
 
LVL 40

Accepted Solution

by:
Vasil Michev (MVP) earned 500 total points
ID: 41729322
Yes, you can ignore the warnings. All you need to do is verify the domain and set its purpose to Exchange Online, which you have already done.

Mail will continue flowing to the old system though, which might or might not be a problem :)
0
 

Expert Comment

by:Steven Rundle
ID: 41729485
I just did an Exchange Online migration.

While in the process, you basically have a hybrid setup. Your on-premise users that you synchronize will become mail contacts to your online exchange organization, and your online users will become mail contacts to your on-premise organization when the mailbox is migrated.

It can get a little  weird when your clients are cached mode and they have outdated OABs or you are missing distribution groups on the online side, and that can be a little bit of a pain as you migrate, but mail should continue to flow between your online and on-premise users without too much trouble. On-premise users will send mail out through your on-premise organization, and online users will send mail out through MS's servers.

Your user accounts will have a couple different attributes that are relevant here. Proxyaddress, which should contain SMTP:<user>@domain.com as well as smtp:<user>@domain,onmicrosoft.com and possibly also smtp:<user>@domain.mail.onmicrosoft.com

External SMTP servers will resolve MX for domain.com and see your on-premise server, and send the mail there. If the the destination user's mailbox has been migrated, they should show up as a mail user and will have a targetAddress attribute that tells your exchange to reroute the mail back out to <user>@domain.onmicrosoft.com.

You just need to have the appropriate connectors set up on each end to handle the mail flow. The Hybrid wizard sets them up for you.
0

Featured Post

MS Dynamics Made Instantly Simpler

Make Your Microsoft Dynamics Investment Count  & Drastically Decrease Training Time by Providing Intuitive Step-By-Step WalkThru Tutorials.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Microsoft Office Picture Manager was included in Office 2003, 2007, and 2010, but not in Office 2013. Users had hopes that it would be in Office 2016/Office 365, but it is not. Fortunately, the same zero-cost technique that works to install it with …
This article lists the top 5 free OST to PST Converter Tools. These tools save a lot of time for users when they want to convert OST to PST after their exchange server is no longer available or some other critical issue with exchange server or impor…
Office 365 is currently available in five editions. Three of them are for business use: Office 365 Business Essentials, Office 365 Business, and Office 365 Business Premium. Two of them are for home/personal use: Office 365 Home and Office 365 Perso…
This is Part 3 in a 3-part series on Experts Exchange to discuss error handling in VBA code written for Excel. Part 1 of this series discussed basic error handling code using VBA. http://www.experts-exchange.com/videos/1478/Excel-Error-Handlin…

749 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question