Creating an Exchange 2010 to Office 365 hybrid;
Login to your Office 365 tenancy – Admin – Exchange Admin – Hybrid – Configure
This downloads the hybrid configuration wizard (HCW). Do the above using IE, initially I used Chrome and I got an error when executing the exe after the download.
In first part the wizard detects the optimal Exchange server to use for the hybrid connection. In my case I only have a single Exchange 2010 server;
Enter your on premises account info to connect to Exchange (you can see I left the tickbox selected to use the credentials I was signed in with. And enter your global admin details for your 365 tenancy
The wizard collects some info and connects to Exchange on premises and Exchange online via PowerShell – then click next
I’ve chosen ‘Full Hybrid Configuration’ as I need fill free/busy, sharing and mail flow
Click ‘enable’ to create the federation trust
You will need to create a txt record in your DNS zone to prove domain ownership
After proving your domain ownership you are asked for information on the mail flow in the hybrid configuration. The default is good for my needs
You are then asked to select the hub transport server for the transport configuration. This is the server that weill host the send connectors for mail transport to Exchange online
You are then asked for the public IP of your hub transport servers. In my case this is a NAT to the internal Ex2010 server
You then need to choose your transport certificate. This needs to be a public cert
You then need to enter the FQDN of your Exchange org. This tells Office 365 where to send email bound for on premises users i.e. before users have been migrated. It creates an outbound connector in Exchange online.
On the next page you simply click update – in the background a number of powershell commands are run which do the all configuration work.
Cloudy, with a chance of networking and IaC 