3679673 - The target database, 'SID', is participating in an availability group and is currently not accessible for queries. Logon  Error: 976.

Your SAP NETWEAVER system runs on Microsoft SQL Server database with Always On Availability Groups high availability (HA).
The SQL error log indicates following error message:

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yyyy-mm-dd  hh:mm:ss   Logon  Error: 976, Severity: 14, State: 1.
yyyy-mm-dd  hh:mm:ss   Logon  The target database, 'SID', is participating in an availability group and is currently not accessible for queries. Either data movement is suspended or the availability replica is not enabled for read access. To allow read-only access to this and other databases in the availability group, enable read access to one or more secondary availability replicas in the group.
For more information, see the ALTER AVAILABILITY GROUP statement in SQL Server Books Online.
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SAP NetWeaver on Microsoft Windows Server Failover Clustering (WSFC) and SQL Server AlwaysOn Availability Groups.

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