We have a customer that has an Exchange 2013 virtual server running on Windows Server 2012R2 on their main site, and they are wanting to move to a hosted Exchange 2016 server in a Data Centre on a separate site.
The Exchange 2016 server is running on Windows Server 2016 and has been patched to CU6. It is also a domain controller in their domain.
A VPN tunnel connects the two sites and there are no restrictions on traffic on the tunnel. It is stable and no pings are dropped.
The 2016 server has been set up with the correct SSL certificate, and the internal and external URL's on the virtual directories all set to the same as the 2013 server in order to prepare for mailbox migrations.
When attempting to move a mailbox to the 2016 server however we get a failure with the message:
Error: MigrationTransientException: There are no available servers running the Microsoft Exchange Mailbox Replication Service.
We have turned up EventLog logging on the MailboxReplication\Service and MailboxReplication\MailboxMove to expert, but do not see any event's being logged on either server.
We have enabled the MRSProxyEnabled switch on both servers. The MailboxReplicationService is running on both servers and set to automatic.
I can't see any errors in any event log to indicate what is going wrong so am at a loss to see what is failing and what we need to configure to make this work.
Are you able to help?