Microsoft SQL Server

Plugin: go.d.plugin Module: mssql

Overview

This collector monitors the health and performance of Microsoft SQL Server instances.

It collects metrics from:

• Performance counters (buffer manager, memory manager, SQL statistics)
• Dynamic management views (DMVs) for wait statistics, locks, and sessions
• Per-database transaction and lock statistics
• SQL Server Agent job status
• Always On Availability Group health, replica states, and per-database synchronization metrics

It connects to the SQL Server instance via TCP using the go-mssqldb driver and executes queries against:

• sys.dm_os_performance_counters - Performance counter values
• sys.dm_exec_sessions - Connection information
• sys.dm_os_wait_stats - Wait statistics
• sys.dm_tran_locks - Lock information
• sys.dm_io_virtual_file_stats - I/O stall (latency) statistics
• sys.dm_os_process_memory - SQL Server process memory
• sys.dm_os_sys_memory - OS physical memory and page file
• sys.master_files - Database file sizes
• msdb.dbo.sysjobs - SQL Agent job status
• sys.dm_hadr_availability_group_states - AG health rollup
• sys.dm_hadr_availability_replica_states - Replica operational state
• sys.dm_hadr_database_replica_states - Database sync queues and rates
• sys.dm_hadr_cluster / sys.dm_hadr_cluster_members - WSFC cluster health
• sys.dm_hadr_database_replica_cluster_states - Failover readiness
• sys.dm_hadr_auto_page_repair - Automatic page repair events
• sys.dm_hadr_ag_threads - AG thread usage (SQL Server 2019+)

This collector is supported on all platforms.

This collector supports collecting metrics from multiple instances of this integration, including remote instances.

The monitoring user requires the VIEW SERVER STATE permission to access DMVs. SQL Agent job monitoring is part of collector startup, so access to msdb.dbo.sysjobs is required. Always On AG monitoring requires VIEW ANY DEFINITION for access to availability group catalog views. On SQL Server 2022+, HADR DMVs may additionally require VIEW SERVER PERFORMANCE STATE.

Microsoft SQL Server can be monitored further using the following other integrations:

• {% relatedResource id=“apps.plugin-apps-Applications” %}Applications{% /relatedResource %}
• {% relatedResource id=“cgroups.plugin-/sys/fs/cgroup-Containers” %}Containers{% /relatedResource %}

Default Behavior

Auto-Detection

By default, it tries to connect to SQL Server on localhost:1433 without authentication. You must configure proper credentials for monitoring.

Limits

The default configuration for this integration does not impose any limits on data collection.

Performance Impact

The collector executes lightweight queries against system views. Most queries complete in milliseconds and have minimal impact on server performance.

Setup

You can configure the mssql collector in two ways:

:::important

UI configuration requires paid Netdata Cloud plan.

:::

Prerequisites

Create monitoring user

Create a SQL Server login with VIEW SERVER STATE permission:

-- Create login
CREATE LOGIN netdata_user WITH PASSWORD = 'YourStrongPassword!';

-- Grant VIEW SERVER STATE (required for DMVs)
GRANT VIEW SERVER STATE TO netdata_user;

-- Grant VIEW ANY DEFINITION (required for Always On AG monitoring)
GRANT VIEW ANY DEFINITION TO netdata_user;

-- Grant VIEW SERVER PERFORMANCE STATE (required for HADR DMVs on SQL Server 2022+)
-- GRANT VIEW SERVER PERFORMANCE STATE TO netdata_user;

-- Grant access to msdb for SQL Agent job monitoring (required)
USE msdb;
CREATE USER netdata_user FOR LOGIN netdata_user;
GRANT SELECT ON dbo.sysjobs TO netdata_user;

-- Optional: Grant access to distribution database for replication monitoring
-- (only if replication is configured)
USE distribution;
CREATE USER netdata_user FOR LOGIN netdata_user;
GRANT SELECT ON dbo.MSreplication_monitordata TO netdata_user;
GRANT SELECT ON dbo.MSpublications TO netdata_user;
GRANT SELECT ON dbo.MSsubscriptions TO netdata_user;

Required permissions:

• VIEW SERVER STATE - Access to dynamic management views
• SELECT on msdb.dbo.sysjobs - SQL Agent job status monitoring

Optional permissions:

• VIEW ANY DEFINITION - Always On Availability Group monitoring
• VIEW SERVER PERFORMANCE STATE - HADR DMVs on SQL Server 2022+
• SELECT on distribution.dbo.MSreplication_monitordata - Replication monitoring
• SELECT on distribution.dbo.MSpublications - Publication information
• SELECT on distribution.dbo.MSsubscriptions - Subscription counts

Configuration

Options

The following options can be defined globally: update_every, autodetection_retry.

via UI

Configure the mssql collector from the Netdata web interface:

1. Go to Nodes.
2. Select the node where you want the mssql data-collection job to run and click the :gear: (Configure this node). That node will run the data collection.
3. The Collectors → Jobs view opens by default.
4. In the Search box, type mssql (or scroll the list) to locate the mssql collector.
5. Click the + next to the mssql collector to add a new job.
6. Fill in the job fields, then click Test to verify the configuration and Submit to save.
   • Test runs the job with the provided settings and shows whether data can be collected.
   • If it fails, an error message appears with details (for example, connection refused, timeout, or command execution errors), so you can adjust and retest.

via File

The configuration file name for this integration is go.d/mssql.conf.

The file format is YAML. Generally, the structure is:

update_every: 1
autodetection_retry: 0
jobs:
  - name: some_name1
  - name: some_name2

You can edit the configuration file using the edit-config script from the Netdata config directory.

cd /etc/netdata 2>/dev/null || cd /opt/netdata/etc/netdata
sudo ./edit-config go.d/mssql.conf

Examples

Basic configuration

Connect to local SQL Server with SQL authentication.

jobs:
  - name: local
    dsn: "sqlserver://netdata_user:password@localhost:1433"

Windows Authentication

Connect using Windows integrated authentication.

jobs:
  - name: local
    dsn: "sqlserver://localhost:1433?trusted_connection=yes"

Named instance

Connect to a named SQL Server instance.

jobs:
  - name: named_instance
    dsn: "sqlserver://netdata_user:password@localhost/INSTANCENAME"

Remote server

Connect to a remote SQL Server.

jobs:
  - name: remote
    dsn: "sqlserver://netdata_user:password@192.168.1.100:1433"

Azure SQL with service principal

Use Microsoft Entra service principal authentication for Azure SQL.

jobs:
  - name: azure_sql_sp
    dsn: "sqlserver://my-server.database.windows.net:1433?database=mydb"
    cloud_auth:
      provider: azure_ad
      azure_ad:
        mode: service_principal
        tenant_id: "00000000-0000-0000-0000-000000000000"
        client_id: "11111111-1111-1111-1111-111111111111"
        client_secret: "super-secret-value"

Azure SQL with managed identity

Use managed identity authentication (system-assigned by default).

jobs:
  - name: azure_sql_mi
    dsn: "sqlserver://my-server.database.windows.net:1433?database=mydb"
    cloud_auth:
      provider: azure_ad
      azure_ad:
        mode: managed_identity

Multi-instance

Note: When you define multiple jobs, their names must be unique.

Monitoring multiple SQL Server instances.

jobs:
  - name: production
    dsn: "sqlserver://netdata_user:password@prod-sql:1433"

  - name: development
    dsn: "sqlserver://netdata_user:password@dev-sql:1433"

With custom function settings

Configure function-specific settings like timeouts and limits.

Warning: Query Store may contain unmasked literal values (PII). Disable functions if not needed or ensure proper access controls.

jobs:
  - name: local
    dsn: "sqlserver://netdata_user:password@localhost:1433"
    functions:
      top_queries:
        limit: 100
        time_window_days: 7
      deadlock_info:
        use_ring_buffer: true
      error_info:
        session_name: custom_errors

Metrics

Metrics grouped by scope.

The scope defines the instance that the metric belongs to. An instance is uniquely identified by a set of labels.

Per Microsoft SQL Server instance

These metrics refer to the entire SQL Server instance.

This scope has no labels.

Metrics:

Per database

These metrics refer to individual databases.

Labels:

Metrics:

Per lock stats

These metrics refer to lock statistics by lock resource type (from performance counters).

Labels:

Metrics:

Per lock resource

These metrics refer to lock resource types (from sys.dm_tran_locks).

Labels:

Metrics:

Per wait type

These metrics refer to individual wait types (from sys.dm_os_wait_stats).

Labels:

Metrics:

Per job

These metrics refer to SQL Server Agent jobs.

Labels:

Metrics:

Per replication

These metrics refer to SQL Server replication publications.

Labels:

Metrics:

Per availability group

These metrics refer to Always On Availability Groups. Auto-detected when HADR is enabled.

Labels:

Metrics:

Per availability group replica

These metrics refer to per-replica state within an Availability Group. Note: on secondary replicas, the replica states DMV returns only local information.

Labels:

Metrics:

Per availability group database replica

These metrics refer to per-database synchronization within an Availability Group.

Labels:

Metrics:

Per WSFC cluster

These metrics refer to the Windows Server Failover Clustering quorum state.

This scope has no labels.

Metrics:

Per WSFC cluster member

These metrics refer to individual WSFC cluster members.

Labels:

Metrics:

Per AG page repair

These metrics refer to automatic page repair events per database in an Availability Group.

Labels:

Metrics:

Alerts

There are no alerts configured by default for this integration.

Troubleshooting

Debug Mode

Important: Debug mode is not supported for data collection jobs created via the UI using the Dyncfg feature.

To troubleshoot issues with the mssql collector, run the go.d.plugin with the debug option enabled. The output should give you clues as to why the collector isn’t working.

• Navigate to the plugins.d directory, usually at /usr/libexec/netdata/plugins.d/. If that’s not the case on your system, open netdata.conf and look for the plugins setting under [directories].

  cd /usr/libexec/netdata/plugins.d/
  

• Switch to the netdata user.

  sudo -u netdata -s
  

• Run the go.d.plugin to debug the collector:

  ./go.d.plugin -d -m mssql
  

  To debug a specific job:

  ./go.d.plugin -d -m mssql -j jobName
  

Getting Logs

If you’re encountering problems with the mssql collector, follow these steps to retrieve logs and identify potential issues:

• Run the command specific to your system (systemd, non-systemd, or Docker container).
• Examine the output for any warnings or error messages that might indicate issues. These messages should provide clues about the root cause of the problem.

System with systemd

Use the following command to view logs generated since the last Netdata service restart:

journalctl _SYSTEMD_INVOCATION_ID="$(systemctl show --value --property=InvocationID netdata)" --namespace=netdata --grep mssql

System without systemd

Locate the collector log file, typically at /var/log/netdata/collector.log, and use grep to filter for collector’s name:

grep mssql /var/log/netdata/collector.log

Note: This method shows logs from all restarts. Focus on the latest entries for troubleshooting current issues.

Docker Container

If your Netdata runs in a Docker container named “netdata” (replace if different), use this command:

docker logs netdata 2>&1 | grep mssql

Connection refused

Ensure SQL Server is running and accepting TCP connections on the configured port. Check that the SQL Server Browser service is running if using named instances.

Login failed

Verify the username and password in the DSN are correct. Ensure SQL Server is configured for mixed mode authentication if using SQL logins.

Permission denied

The monitoring user needs VIEW SERVER STATE permission. Grant it with: GRANT VIEW SERVER STATE TO netdata_user;