Currently, our JIRA system relies solely on a single database, which poses a significant risk to our operations. When we perform system updates and routine maintenance, it results in prolonged downtime and necessitates multiple restarts, which we have to do on a monthly basis. As per our organizational mandates, we are obligated to execute planned operational maintenance, upgrade initiatives, security patch applications, and product support activities with minimal disruption.

To tackle these challenges, we are exploring the option of transitioning our JIRA Standalone MSSQL VM into an MSSQL FCI setup to enhance operational activities and ensure high availability.

We are discussing an MSSQL FCI Setup which is going to have a shared storage but on VM level there would be high availability to ease our operational activities. Jira is connecting with MSSQL through it's SQL Instance either named instance or default instance along configured port, we are not able to understand what MSSQL FCI Setup creates issues for Jira that support is fully denying and not accepting it though it's going to give same connectivity but underlaying high availability on VM level.

https://www.starwindsoftware.com/blog/always-on-availability-groups-vs-failover-cluster/

As of today, the only clustered database solution supported is Pg-pool II - https://confluence.atlassian.com/adminjiraserver0910/supported-platforms-1282245150.html