Exchange 2019 Migration Endpoint

[Bankesy]

Good afternoon,

 

Could somebody help me with where I'm going wrong please?

 

I'm trying to create a migration endpoint in Exchange 2019 (because I think I need to in order to move some mailboxes from on prem) but I just can't seem to figure out what the wizard is asking for when setting it up. I think there was previously a migration endpoint configured but seems like maybe updates\restart wiped it out.

 

The wizard seems to want an example e-mail to migrate, then some domain\administrator credentials, pretty sure I've got all of that correct but then I just get an error telling me that the migration point couldn't be created via AutoDiscover and that I need to enter the FQDN of the server where MRS is installed (which I presume is the Exchange server).

 

This is followed by an error telling me that a connection couldn't be established.

 

Basically I'm trying to fix the weird hybrid mess we've ended up in with some mailboxes on prem, some in cloud (some users appear to have on prem and cloud mailboxes) and only only one way communication between on prem and cloud (no communication between cloud mailboxes and on prem).

 

...rant over

[3s-gtech]

Is your autodiscover address set up and working? It’s easy to skip this when building Exchange!

[chaplic]

Oh dear oh dear oh dear. It sounds like setting up MRS is the start of your problems.

 

if its any consolation I did some work for a bank that accidentally had 10,000 duplicate mailboxes in O365

 

Go look at your URLs in Exchange 2019 ECP to figure out what your URLs are, it needs to be a name resolveable by the internet (so not exh2019.domain.local). Then check they are published to the internet, with the correct cert, up-to-date. You don’t need working autodiscover externally as you can pop in the server details (as prompted), but it makes life easier.

 

I would also suspect your organisational relationship might be problematic too, but one thing at a time!

 

https://testconnectivity.microsoft.com/ Is quite handy though some tests are a little misleading.

[Bankesy]

Hiya,

 

I don't exactly know what was or wasn't setup, I just inherited it a few months back.

 

I don't have many duplicate mailboxes in O365 but would be nice to clear them up and know that communications work both ways so we can migrate.

[chaplic]

I sensed it wasn’t your doing

First you need to determine why youve got a duplicate. It will happen when

 

a) an account from AD is projected into Azure AD, and

b) that account is licensed for Exchane

c) a variety of on prem AD attributes are not filled in - MsExchMailboxGuid being the one that comes to mind

 

Basically if exo thinks you don’t have a mailbox on prem and are licensed, it will create a mailbox. Luckily there’s a way to deal with it (wasn’t when I was a lad and it was all fields)

https://learn.microsoft.com/en-us/exchange/troubleshoot/user-and-shared-mailboxes/mailbox-exists-exo-onpremises

 

As said, we need your internal exchange published to the internet for this to work. Some people just expose it to Microsoft IPs which is do-able but these do change over time.

 

 

 

We need to know the external URLs, determine they are connectable externally, determine the certificate is good, then lets worry about things like org relationship and free/busy time

 

 

 

Get-webservicesvirtualdirectory

 

 

Should give you a clue to the URLs in play. Visit them externally and see if you get a connection and no SSL error

[Bankesy]

@chaplic

 

Seems like it might have been my doing actually, I think where I enabled the licenses for Exchange Online but was running Powershell commands to create mailbox on prem.

 

Seems to be fine now that I am running the correct commands to only create the mailbox in the cloud.

 

Also, I haven't worked with Exchange a lot but I think I've got my head around how the Lets Encrypt certificate expires every three months and then needs adding to ISS, enabling for SMTP and then selecting in the Hybrid Config Wizard.

 

Thanks

Edited October 24, 2022 by Bankesy