General steps
- Set up an on-premise AD with forest name johnfoo.tk
- get a free domain from freenom (johnfoo.tk)
- In Freenom, configure to use your own DNS server, pointing to on-prem DC IP
- set up Azure AD
- create an Azure account for AAD Connect, make it Global Admin
- create an AD service account for AD, give it DC Sync permission (or let AD Connect create for you)
- Add and verify Custom Domain in AAD. Create the TXT record on your AD DNS. The "@" -named record required by Azure is equivalent of "(same as parent)" record in Windows DNS. Just leave the record name blank when create the TXT record.
- Install AD Connect, enable
- PHA (recommended, for auth fault tolerance, or PTA). Of course, use federation is also possible depending on if you are using ADFS right now on prem
- Enable Seamless SSO (for on prem users SSO into Azure)
- Be careful what attribute to use for join rule (?). UPN is a good candidate. Unless on prem users are already having email address, using mail for linkage will not work
Manually join Windows clients into Azure AD
- Enable join/register option for regular users: AAD|Devices|Device Settings|Users may join devices to Azure AD
- On Win client, Accounts, connect to work, then select "join this device to Azure AD", follow on screen instructions
- use "AzureAD\azureUPN" to log into the newly joined machine (e.g. AzureAD\jlan@johnfoo.tk)
Manually register Windows clients into Azure AD
- Same steps as above, but in step 2, do not select "join this device to AZure AD", instead, just click on "next" button
Create a B2C Tenant
- Run "az provider register --namespace Microsoft.AzureActiveDirectory"
- Follow on screen instruction
Grant Admin access to an Azure-joined machine
- Tenant wide permission
- Azure AD has a "Device administrators" role that is used for this purpose
- Go to Devices | Device Settings | Manage Addtional local administrators on all Azure AD Joined devices | +assignment
- Individual machine
- Locally on the machine, using Account Settings to elivate a user
- "net localgroup administrators /add "Contoso\username" for adding on-prem user
- "net localgroup administrators /add "AzureAD\UserUpn" for adding Azure user
- use MDM solution
Enabled Hybrid AD join
- Run ADC, select Configure | additional tasks | Configure device options
- Follow on screen instruction