What is the best way to shut down a 2 node availability group This fall we will be powering down the whole data center to replace a defective power module. There is no DR site to move anything to, everything last bit of the company resides in one DC at one location.
What is the best way to shut down a 2 node availability group? Should I remove the databases from the AG then power off the servers? When bringing the servers online after the power work is done. Should I have the share witness server up first, then the primary server and second server last? Then re-add the databases to the AG? We run Windows 2008 R2, and SQL Server Enterprise 2012 core edition in a VMware environment.
No need to touch the AGs.  You should have full set of database backups on a USB external drive or on Azure Blob Storage before you shut down the datacenter.
Just shut down the secondary node first, then the primary.  Bring them back up in the reverse order.  Boot up your domain controller VMs first, then any other supporting infrastructure, like the VM hosting the FSW.  When you bring the VM hosting the primary replica online it should establish quorum and come online.