- 2012 or newer (Plugin support aligned with the [official Microsoft SQL Server support](https://docs.microsoft.com/en-us/sql/sql-server/end-of-support/sql-server-end-of-life-overview?view=sql-server-ver15#lifecycle-dates))
- End-of-life SQL Server versions are not guaranteed to be supported by Telegraf. Any issues with the SQL Server plugin for these EOL versions will
## "database_type" enables a specific set of queries depending on the database type. If specified, it replaces azuredb = true/false and query_version = 2
## In the config file, the sql server plugin section should be repeated each with a set of servers for a specific database_type.
## Possible values for database_type are - "AzureSQLDB" or "AzureSQLManagedInstance" or "SQLServer"
## Queries enabled by default for database_type = "AzureSQLDB" are -
### Support for Azure Active Directory (AAD) authentication using [Managed Identity](https://docs.microsoft.com/en-us/azure/active-directory/managed-identities-azure-resources/overview)
Azure SQL Database supports 2 main methods of authentication: [SQL authentication and AAD authentication](https://docs.microsoft.com/en-us/azure/azure-sql/database/security-overview#authentication). The recommended practice is to [use AAD authentication when possible](https://docs.microsoft.com/en-us/azure/azure-sql/database/authentication-aad-overview).
AAD is a more modern authentication protocol, allows for easier credential/role management, and can eliminate the need to include passwords in a connection string.
To enable support for AAD authentication, we leverage the existing AAD authentication support in the [SQL Server driver for Go](https://github.com/denisenkom/go-mssqldb#azure-active-directory-authentication---preview)
- Configure "system-assigned managed identity" for Azure resources on the Monitoring VM (the VM that'd connect to the SQL server/database) [using the Azure portal](https://docs.microsoft.com/en-us/azure/active-directory/managed-identities-azure-resources/qs-configure-portal-windows-vm).
- On the database being monitored, create/update a USER with the name of the Monitoring VM as the principal using the below script. This might require allow-listing the client machine's IP address (from where the below SQL script is being run) on the SQL Server resource.
```sql
EXECUTE ('IF EXISTS(SELECT * FROM sys.database_principals WHERE name = ''<Monitoring_VM_Name>'')
BEGIN
DROP USER [<Monitoring_VM_Name>]
END')
EXECUTE ('CREATE USER [<Monitoring_VM_Name>] FROM EXTERNAL PROVIDER')
EXECUTE ('GRANT VIEW DATABASE STATE TO [<Monitoring_VM_Name>]')
```
- On the SQL Server resource of the database(s) being monitored, go to "Firewalls and Virtual Networks" tab and allowlist the monitoring VM IP address.
- On the Monitoring VM, update the telegraf config file with the database connection string in the following format. Please note AAD based auth is currently only supported for Azure SQL Database and Azure SQL Managed Instance (but not for SQL Server), as described [here](https://docs.microsoft.com/en-us/azure/azure-sql/database/security-overview#authentication).
- On the Monitoring VM, update the telegraf config file with the database connection string in the following format.
- On the Monitoring VM, update the telegraf config file with the database connection string in the following format. The connection string only provides the server and database name, but no password (since the VM's system-assigned managed identity would be used for authentication).
- Please note AAD based auth is currently only supported for Azure SQL Database and Azure SQL Managed Instance (but not for SQL Server), as described [here](https://docs.microsoft.com/en-us/azure/azure-sql/database/security-overview#authentication).
**Note**: Version 2 queries are not backwards compatible with the old queries. Any dashboards or queries based on the old query format will not work with the new format. The version 2 queries only report raw metrics, no math has been done to calculate deltas. To graph this data you must calculate deltas in your dashboarding software.
- *Server properties*: Number of databases in all possible states (online, offline, suspect, etc.), cpu count, physical memory, SQL Server service uptime, and SQL Server version. In the case of Azure SQL relevant properties such as Tier, #Vcores, Memory etc.
- *Wait stats*: Wait time in ms, number of waiting tasks, resource wait time, signal wait time, max wait time in ms, wait type, and wait category. The waits are categorized using the same categories used in Query Store.
- *Schedulers* - This captures `sys.dm_os_schedulers`.
- *SqlRequests* - This captures a snapshot of `sys.dm_exec_requests` and `sys.dm_exec_sessions` that gives you running requests as well as wait types and
- *VolumeSpace* - uses `sys.dm_os_volume_stats` to get total, used and occupied space on every disk that contains a data or log file. (Note that even if enabled it won't get any data from Azure SQL Database or SQL Managed Instance). It is pointless to run this with high frequency (ie: every 10s), but it won't cause any problem.
- *Cpu* - uses the buffer ring (`sys.dm_os_ring_buffers`) to get CPU data, the table is updated once per minute. (Note that even if enabled it won't get any data from Azure SQL Database or SQL Managed Instance).
- Resource governance stats from `sys.dm_instance_resource_governance`
- *Azure SQL Database* in addition to other stats
- Stats from `sys.dm_db_wait_stats`
- Resource governance stats from `sys.dm_user_db_resource_governance`
- Stats from `sys.dm_db_resource_stats`
#### database_type = "AzureSQLDB
These are metrics for Azure SQL Database (single database) and are very similar to version 2 but split out for maintenance reasons, better ability to test,differences in DMVs:
- AzureSQLDBDatabaseIO: IO stats from `sys.dm_io_virtual_file_stats` including resource governance time, RBPEX, IO for Hyperscale.
- AzureSQLDBMemoryClerks: Memory clerk breakdown from `sys.dm_os_memory_clerks`.
= AzureSQLDBResourceGovernance: Relevant properties indicatign resource limits from `sys.dm_user_db_resource_governance`
- AzureSQLDBPerformanceCounters: A select list of performance counters from `sys.dm_os_performance_counters` including cloud specific counters for SQL Hyperscale.
- AzureSQLDBWaitstats: Wait time in ms from `sys.dm_db_wait_stats`, number of waiting tasks, resource wait time, signal wait time, max wait time in ms, wait type, and wait category. The waits are categorized using the same categories used in Query Store. These waits are collected only as of the end of the a statement. and for a specific database only.
- *AzureSQLOsWaitstats*: Wait time in ms from `sys.dm_os_wait_stats`, number of waiting tasks, resource wait time, signal wait time, max wait time in ms, wait type, and wait category. The waits are categorized using the same categories used in Query Store. These waits are collected as they occur and instance wide
- *AzureSQLDBRequests: Requests which are blocked or have a wait type from `sys.dm_exec_sessions` and `sys.dm_exec_requests`
- *AzureSQLDBSchedulers* - This captures `sys.dm_os_schedulers` snapshots.
#### database_type = "AzureSQLManagedInstance
These are metrics for Azure SQL Managed instance, are very similar to version 2 but split out for maintenance reasons, better ability to test, differences in DMVs:
- AzureSQLMIDatabaseIO: IO stats from `sys.dm_io_virtual_file_stats` including resource governance time, RBPEX, IO for Hyperscale.
- AzureSQLMIMemoryClerks: Memory clerk breakdown from `sys.dm_os_memory_clerks`.
- AzureSQLMIResourceGovernance: Relevant properties indicatign resource limits from `sys.dm_instance_resource_governance`
- AzureSQLMIPerformanceCounters: A select list of performance counters from `sys.dm_os_performance_counters` including cloud specific counters for SQL Hyperscale.
- AzureSQLMIOsWaitstats: Wait time in ms from `sys.dm_os_wait_stats`, number of waiting tasks, resource wait time, signal wait time, max wait time in ms, wait type, and wait category. The waits are categorized using the same categories used in Query Store. These waits are collected as they occur and instance wide
- AzureSQLMIRequests: Requests which are blocked or have a wait type from `sys.dm_exec_sessions` and `sys.dm_exec_requests`
- AzureSQLMISchedulers - This captures `sys.dm_os_schedulers` snapshots.
#### database_type = "SQLServer
- SQLServerDatabaseIO: IO stats from `sys.dm_io_virtual_file_stats`
- SQLServerMemoryClerks: Memory clerk breakdown from `sys.dm_os_memory_clerks`, most clerks have been given a friendly name.
- SQLServerPerformanceCounters: A select list of performance counters from `sys.dm_os_performance_counters`. Some of the important metrics included:
- *Activity*: Transactions/sec/database, Batch requests/sec, blocked processes, + more
- *Availability Groups*: Bytes sent to replica, Bytes received from replica, Log bytes received, Log send queue, transaction delay, + more
- SQLServerProperties: Number of databases in all possible states (online, offline, suspect, etc.), cpu count, physical memory, SQL Server service uptime, and SQL Server version. In the case of Azure SQL relevant properties such as Tier, #Vcores, Memory etc.
- SQLServerWaitStatsCategorized: Wait time in ms, number of waiting tasks, resource wait time, signal wait time, max wait time in ms, wait type, and wait category. The waits are categorized using the same categories used in Query Store.
- SQLServerSchedulers - This captures `sys.dm_os_schedulers`.
- SQLServerRequests - This captures a snapshot of `sys.dm_exec_requests` and `sys.dm_exec_sessions` that gives you running requests as well as wait types and
blocking sessions.
- SQLServerVolumeSpace - uses `sys.dm_os_volume_stats` to get total, used and occupied space on every disk that contains a data or log file. (Note that even if enabled it won't get any data from Azure SQL Database or SQL Managed Instance). It is pointless to run this with high frequency (ie: every 10s), but it won't cause any problem.
- SQLServerCpu - uses the buffer ring (`sys.dm_os_ring_buffers`) to get CPU data, the table is updated once per minute. (Note that even if enabled it won't get any data from Azure SQL Database or SQL Managed Instance).
- SQLServerAvailabilityReplicaStates: Collects availability replica state information from `sys.dm_hadr_availability_replica_states` for a High Availability / Disaster Recovery (HADR) setup
- SQLServerDatabaseReplicaStates: Collects database replica state information from `sys.dm_hadr_database_replica_states` for a High Availability / Disaster Recovery (HADR) setup
The guiding principal is that all data collected from the same primary DMV ends up in the same measure irrespective of database_type.
`sqlserver_database_io` - Used by AzureSQLDBDatabaseIO, AzureSQLMIDatabaseIO, SQLServerDatabaseIO, DatabaseIO given the data is from `sys.dm_io_virtual_file_stats`
`sqlserver_waitstats` - Used by WaitStatsCategorized,AzureSQLDBOsWaitstats,AzureSQLMIOsWaitstats
`sqlserver_server_properties` - Used by SQLServerProperties, AzureSQLDBServerProperties , AzureSQLMIServerProperties,ServerProperties
`sqlserver_memory_clerks` - Used by SQLServerMemoryClerks, AzureSQLDBMemoryClerks, AzureSQLMIMemoryClerks,MemoryClerk
`sqlserver_performance` - Used by SQLServerPerformanceCounters, AzureSQLDBPerformanceCounters, AzureSQLMIPerformanceCounters,PerformanceCounters
`sys.dm_os_schedulers` - Used by SQLServerSchedulers,AzureSQLDBServerSchedulers, AzureSQLMIServerSchedulers
The following Performance counter metrics can be used directly, with no delta calculations:
All collection versions (version 1, version 2, and database_type) support an optional plugin health metric called `sqlserver_telegraf_health`. This metric tracks if connections to SQL Server are succeeding or failing. Users can leverage this metric to detect if their SQL Server monitoring is not working as intended.
In the configuration file, toggling `health_metric` to `true` will enable collection of this metric. By default, this value is set to `false` and the metric is not collected. The health metric emits one record for each connection specified by `servers` in the configuration file.
The health metric emits the following tags:
-`sql_instance` - Name of the server specified in the connection string. This value is emitted as-is in the connection string. If the server could not be parsed from the connection string, a constant placeholder value is emitted
-`database_name` - Name of the database or (initial catalog) specified in the connection string. This value is emitted as-is in the connection string. If the database could not be parsed from the connection string, a constant placeholder value is emitted
The health metric emits the following fields:
-`attempted_queries` - Number of queries that were attempted for this connection
-`successful_queries` - Number of queries that completed successfully for this connection
-`database_type` - Type of database as specified by `database_type`. If `database_type` is empty, the `QueryVersion` and `AzureDB` fields are concatenated instead
If `attempted_queries` and `successful_queries` are not equal for a given connection, some metrics were not successfully gathered for that connection. If `successful_queries` is 0, no metrics were successfully gathered.
