Thursday, 17 December 2015

Exchange 2013 to 2016 Migration (Part 5)

Introduction


In part 4, we created the mailbox databases on our new Exchange 2016 server and moved the public folders and mailboxes to this new server.

In this next part, we will migrate mail flow so that external incoming and outgoing email is processed by our Exchange 2016 server so that we can get one step closer to decommissioning our Exchange 2013 server.

To read other parts in this series, go to:


Migrate incoming mail flow to Exchange 2016


This will depend on how your current mail flow is configured. Your public MX records will resolve to a hostname which in turn resolves to an IP address or multiple IP addresses. From here these IPs may be for a cloud email filter or an on premises email filter which processes email before handing off to Exchange or the IPs may just resolve to your current Exchange 2013 servers.


Email filter present


If you’re using an email filter then to migrate mail flow to your Exchange 2016 server, you need to just configure your mail filter to hand off the email to your new Exchange 2016 server rather than your Exchange 2013 server. Ensure that port 25 is open from your mail filter to your Exchange 2016 server.


No email filter present


If you’re not using an email filter before email is delivered to Exchange then you need to open up port 25 from the internet to your Exchange 2016 server and then change your MX record so that email is now delivered to the Exchange 2016 server first. You will need to use your public DNS provider such as GoDaddy or 123-reg to change your MX records.


Migrate outgoing mail flow to Exchange 2016


Again, this step depends on whether your current Exchange 2013 server sends out email through a smart host which then relays out the email to the internet. You can figure this out by running this command:

Get-SendConnector | fl Name,SmartHosts,SourceTransportServers,AddressSpaces

image

Above, we can see that there is no smart host set so that means our Exchange 2013 server, litex01, sends out email directly to the internet.


Smart host present


If you are using a smart host then you need to need to configure it so that it will accept and relay email from the Exchange 2016 server IP. Once done, you need to change the transport servers on the send connector:

Set-SendConnector "Internet Send Connector" -SourceTransportServers litex02

image

You can then send some test emails using Outlook or OWA to test this change. Always make sure that you have valid reverse DNS and a valid SPF record see the articles below for more information:


No smart host present


If you’re not using a smart host then you need to create a new reverse DNS record (PTR record) for your new Exchange 2016 public IP. See here for more information. You’ll also need to add the Exchange 2016 public IP to your SPF record – see here for more information.

Once you’ve done this, run the same command to configure your send connector so that email is sent to the internet directly using our Exchange 2016 server, litex02:

Set-SendConnector "Internet Send Connector" -SourceTransportServers litex02

image

Conclusion

In this part, we’ve migrated incoming and outgoing external mail flow to Exchange 2016 which means that Exchange is no longer required for this service. As you can see we’re gradually migrating services from our Exchange 2013 server in preparation for decommissioning it.

In the next part, we’ll go through the preparation steps before we go ahead and decommission our Exchange 2013 server. Click here to go to part 6.

1 comment:

  1. This was an incredibly helpful and thorough write up for upgrading from Exchange 2013 to 2016. Thank you so much!

    One question I have regarding SPAM Filters that were setup using ECP on Exchange 2013, stuff like bypass SPAM filter domains, blocked ip addresses etc. How are those migrated to Exchange 2016?

    ReplyDelete