Hi @Cédric,
Thank you for reaching out and welcome to Microsoft Q&A.
Quote from Microsoft Licensing Reference Guide (start from the page of 26):
Two secondary servers used for failover support do not need to be separately licensed for SQL Server as long as they are passive, and the primary SQL Server is covered with subscription licenses or licenses with active SA. If a server is marked to read and serving data, such as reports to clients running active SQL Server workloads, or performing any “work” except for maintenance related operations mentioned above, then it must be licensed for SQL Server.
For Always On Availability Groups licensing, when secondary replicas are actively used to support high availability, disaster recovery, and read-scale balancing, they must be fully licensed accordingly. You'd better check with your Microsoft rep to be certain though.
As we are not doing anything more than what is proposed in the dashboard, is a license change necessary for these secondary nodes?
Since there is nothing beyond the regulations, I don't think it is necessary to change the license. I am not an expert in this field. If you still have concerns, you can refer to Olaf's answer and consult a professional.
Feel free to share your issue here if you have any confusions.
Best regards,
Lucy Chen
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