The other last night I received a call from a co-worker who added a Windows firewall rule to a production AWS EC2 machine running Server 2016. Soon after he couldn’t access the server via RDP nor were any of the IIS sites loading.
Of course a snapshot was not created prior to the change, because “It worked in Test”.
At first I thought we might be up a creek and restoring from an older backup. But, then I remembered AWS Systems Manager and the ability to send commands to an AWS EC2 machine via the AWS console.
Below are the quick steps I took to disable the Windows Firewall using AWS Systems Manager to regain access into the EC2 machine.