What’s the Best Way to Transition to a Serverless Setup Across Multiple Sites?

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I recently worked on a similar transition for a client. Key steps involved include moving to a hybrid environment (or directly to Microsoft Entra ID), migrating file shares to OneDrive and SharePoint, and eventually decommissioning your on-prem Active Directory and servers. Shift your DHCP and DNS services to your firewall in the process. It can be a bit of work, but it greatly eases management in the long run.

Keep in mind the geographic proximity of your locations to Azure or AWS data centers. Performance for file shares from an on-prem setup to cloud solutions can vary significantly. Depending on your configuration, costs might go up while performance could dip unless you’re using virtual desktops to counteract that.

To make the switch, you'll likely need to position most of your services in the Microsoft cloud. Start with a hybrid Active Directory setup to get everything in sync. You can use Entra ID and Azure to replace your AD, and for file storage, migrate your data to SharePoint and OneDrive. Your Cisco equipment can handle DHCP and manage the SD-WAN connections as well. Just remember, this will take some time and coordination, especially moving all your local files online before decommissioning any servers. Once your on-prem servers are gone, managing your SD-WAN becomes simpler too!

You've already got a good framework! If there are no other workloads, consider cloud-joining your PCs and migrating files to SharePoint Online. Your Cisco gear should manage DHCP effortlessly across the locations. Transitioning can be done step-by-step with a hybrid setup if that’s easier. Don't forget about printing needs, and be mindful of DNS and endpoint filtering if required!