I currently have a single default instance of SQL2017 Standard on a 2-node cluster. Against my preference, I need to setup a second instance on the cluster (the new database requires some users to have sysadmin so they can't be hosted alongside other databases on the existing instance :-( )
On the existing cluster, only the Active node is licenced.
When I install a second instance, do I HAVE to use a separate set of disks, or can it be installed on the same disks as the default instance? (I'm not even sure if it is possible, let alone whether it is preferable) Am planning to host BOTH instances on a single node - resource requirements are not high, so can be managed.
My concern is that one of the instances 'could' fail over to the second node. But the second node is not licenced, so am not allowed to run an instance on each node (though I believe I do have a short period to fail it back).
Presumably I need to implement some monitoring to alert me if EITHER instance fails over, and get it failed back ASAP.