Since only one SQL server is active in an Active\Passive cluster, you should not require multiple Monitor licenses.
Currently, we are offering a 50% discount for passive cluster nodes. We’ll continue to review our pricing structure over time.
Why do we charge money for passive nodes at all? Covering your passive nodes with monitoring is necessary to ensure that when a failover occurs, the passive node is in a healthy state, and the failover will be able to succeed. However, passive nodes don’t (usually) have complex performance characteristics, hence the discount.
Or at least this could be an option. For those who want Windows data from the passive nodes, they could choose to use an extra license. But at the very least, monitoring of the active node without needing two licenses should be allowed.
P Curd commented
Mirroring is another area where you have two or three machines running on a single SQL license - I couldn't convince finance to let me buy three licences of monitoring to cover one license of SQL. I expect to have to pay more for it since it's doing more work, but I can't justify three times the price.
Thanks a lot for your feedback. We will definitely try to improve licensing.
Red Gate does offer some discount on cluster license. So if you are buying SQL Monitor license for cluster then please do mention this to Sales team and they can add some discount to your license purchase.
Nathan Bell commented
You should offer price points either by per instance or by per machine. This woudl grant users the ability to license either way for shops that run many instance on one server and vice-versa.