"AlwaysOn Availability Groups" were added to SQL client support in .NET Framework 4.5 for high-availability disaster recovery. This included the "MultiSubnetFailover" SQL client connection option. Is this supported in Symantec Endpoint Protection Manager (SEPM) and its connection to a SQL database?
A SEPM will always try to reconnect to SQL if an issue is encountered. SEPM can support using "multiSubnetFailover=true" in the SQL connection string but this option must be manually inserted into the JDBC URL in [SEPM]\tomcat\conf\Catalina\localhost\ROOT.xml. Note that administrative rights are required to edit SEPM configuration files.
Restart the SEPM services after adding "multiSubnetFailover=true" into the JDBC URL.
Sample ROOT.xml with multiSubnetFailover option inserted: