In the failover cluster manager (FCM) right click the cluster and under more actions you can set the cluster quorum.
In the next screen you can do the default/select/advanced config.
I choose the advanced , This is a fresh Cluster and currently there is only one node.
But you can make a selection of the nodes that can vote, So if you have a node that is less important and or you don’t want to have the vote you can un select them. And you can find this easily in the nodes assigned vote
This step you can create a fileserver witness or a disk witness. Remember when creating your cluster and all disk are presented to the cluster the smallest disk is auto assign to be the witness disk. unless there is only one disk then this disk is used as quorum even if this disk is several TB.
as you can see in the disks the Quorum is configured.
and yes all these steps can be don in PowerShell
Set-ClusterQuorum –Cluster Left01 -NodeAndDiskMajority "Cluster Disk 2"
but now for changing the quorum ? yes the same steps are needed
but in the disk selection there is already a disk selected and you can’t use two disks so flip the check box for the other disk and you are ready to go.
Set-ClusterQuorum –Cluster Left01 -NodeAndDiskMajority "Cluster Disk 3"
So now downtime no reboots and flip it back to disk 2 easy