Partial tenant migration w/ ShareGate--Limiting access of the other side?

Posted by mixduptransistor@reddit | sysadmin | View on Reddit | 6 comments

We're a M365 shop. We are divesting a small portion of our business to a third party, and the acquiring company is entitled by the agreement to email of divested employees, SharePoint sites for the divested departments, and MS Teams teams for the divested departments

They do a lot of these acquisitions and have a fairly standard process where they will connect to our tenant with ShareGate and migrate what they need. I think most of the time they do full acquisitions, not partial ones

Our issue is that Sharegate apparently needs full permissions into our entire tenant, and we're obviously hesitant to do that

So my question to the peanut gallery is: Is there a way to mitigate this risk? We're waiting to hear back from ShareGate support if the new-ish Exchange Online RBAC for Applications can be applied to the app registration, but that will only solve our email problem

They've suggested that we use a VM in our environment for the migration and we can record/shoulder surf what they're doing, but I don't know enough about ShareGate to know if that is viable. Is it an on-prem tool, or is it a cloud tool? Is it possible for us to lock it so that it can only be used on a machine we control? Seems like if it's a cloud tool that's not going to work