MariaDB

MariaDB speaks the MySQL wire protocol, so the OpenTelemetry Collector's mysql receiver monitors it without a separate exporter. It connects over TCP on port 3306, runs SHOW GLOBAL STATUS / SHOW GLOBAL VARIABLES and performance_schema queries, and emits 31 metrics per scrape - query throughput, connection health, lock contention, buffer-pool pressure, and InnoDB internals. This guide sets up a monitoring user, configures the receiver, and ships metrics to base14 Scout.

Prerequisites

Requirement	Minimum	Recommended
MariaDB	10.5	12.3+
OTel Collector Contrib	0.90.0	latest
base14 Scout	Any	—

Before starting:

• MariaDB must be reachable from the host running the Collector.
• A superuser account to create the monitoring user once.
• performance_schema enabled for statement-event and table-lock-wait coverage.
• OTel Collector installed - see Docker Compose Setup.
• A Scout account and OTLP endpoint.

What You'll Monitor

Metrics are grouped into three tiers by how you use them. Scrape Core always, alert on Operational, and reach for Diagnostic during an incident or capacity review.

Core - is it up and serving

Metric	What it tells you
mysql.uptime	Seconds since server start - reachability and restart detection.
mysql.query.count	Statements executed; the headline throughput KPI.

Operational - what to alert on

Group	Metrics	What it tells you
Connection health	mysql.connection.count, mysql.connection.errors	Connections opened and connection failures by cause.
Latency	mysql.query.slow.count	Queries over long_query_time - regressions and missing indexes.
Contention	mysql.locks, mysql.row_locks	Table locks (immediate vs waited) and InnoDB row-lock waits / time.
Saturation	mysql.threads	Threads connected / running / cached against the server max.
Cache pressure	mysql.buffer_pool.usage	Buffer-pool bytes by state; working set vs pool size.
Query spill	mysql.tmp_resources	Temp tables and files, memory vs disk - sort and join spill.

Diagnostic - for investigation and tuning

Higher cardinality (these series drive most of the per-scrape data-point count). Keep them available for incident work; drop them in production with a filter processor if you need to control volume.

Group	Metrics	When you reach for it
Command / handler breakdown	mysql.commands, mysql.handlers, mysql.query.client.count	Which statement and storage-engine handler calls dominate.
InnoDB internals	mysql.operations, mysql.page_operations, mysql.log_operations, mysql.double_writes	Row, page, redo-log, and doublewrite-buffer activity.
Buffer-pool detail	mysql.buffer_pool.data_pages, mysql.buffer_pool.limit, mysql.buffer_pool.operations, mysql.buffer_pool.page_flushes, mysql.buffer_pool.pages	Clean/dirty pages, capacity, read/write requests, flush rate.
Query workload	mysql.sorts, mysql.joins, mysql.prepared_statements	Sort and join types, prepared-statement load.
Resource accounting	mysql.opened_resources, mysql.table_open_cache, mysql.client.network.io	Files / tables / definitions opened, cache hits/misses, client bytes.
Per-table stats	mysql.table.rows, mysql.table.size, mysql.table.average_row_length	Row count, data/index size, and average row length per table.

The following are enabled in the config but only emit in specific contexts - keep them on so they surface when those conditions arise:

• mysql.replica.sql_delay, mysql.replica.time_behind_source - emit only when a replica is configured.
• mysql.statement_event.count, mysql.statement_event.wait.time - require populated performance_schema digest tables.
• mysql.table.lock_wait.read.count / .read.time / .write.count / .write.time - emit only when contended table-lock waits occur.

Full metric reference: OTel MySQL Receiver.

Key Alerts to Configure

Threshold guidance for the most useful Operational-tier series. These are starting points; tune them to your workload.

Metric	Threshold	Why it matters
rate(mysql.connection.errors)	Rising above 0	Clients can't connect; check max_connections, auth, and network.
mysql.threads{kind=connected}	Near the server max	Approaching max_connections; add pooling or raise the cap.
rate(mysql.query.slow.count)	Rising vs baseline	Query regressions or missing indexes; inspect the slow log.
mysql.row_locks (wait time)	Rising	Transactions blocking; review lock ordering and hot rows.
mysql.tmp_resources{kind=disk_tables}	Rising	tmp_table_size too small or unindexed sorts; tune queries.
mysql.buffer_pool.usage (dirty/free ratio)	Shifting toward full	Working set exceeds the pool; consider innodb_buffer_pool_size.

Access Setup

Create a dedicated MariaDB user with minimal monitoring privileges:

MariaDB monitoring user setup

CREATE USER 'otel_monitor'@'%' IDENTIFIED BY '<your_password>';
GRANT PROCESS, REPLICATION CLIENT ON *.* TO 'otel_monitor'@'%';
GRANT SELECT ON performance_schema.* TO 'otel_monitor'@'%';
FLUSH PRIVILEGES;

Minimum required permissions:

Permission	Purpose
PROCESS	Access to SHOW GLOBAL STATUS and SHOW GLOBAL VARIABLES
REPLICATION CLIENT	Access to SHOW REPLICA STATUS for replication metrics
SELECT ON performance_schema.*	Statement events, table I/O, and lock-wait metrics

No write permissions are needed. The Collector only reads metrics.

Ensure performance_schema and the slow query log are enabled:

my.cnf

[mysqld]
performance_schema = ON
slow_query_log = ON
long_query_time = 1

Test connectivity with the monitoring user:

Verify access

mariadb -h <mariadb-host> -P 3306 -u otel_monitor -p \
  -e "SELECT version();"

Configuration

config/otel-collector.yaml

receivers:
  mysql:
    endpoint: ${env:MARIADB_HOST}:3306
    username: ${env:MYSQL_USER}
    password: ${env:MYSQL_PASSWORD}
    collection_interval: 10s
    allow_native_passwords: true

    tls:
      insecure: true
      insecure_skip_verify: true

    metrics:
      # Disabled by default - enable for full observability
      mysql.client.network.io:
        enabled: true
      mysql.commands:
        enabled: true
      mysql.connection.count:
        enabled: true
      mysql.connection.errors:
        enabled: true
      mysql.joins:
        enabled: true
      mysql.query.client.count:
        enabled: true
      mysql.query.count:
        enabled: true
      mysql.query.slow.count:
        enabled: true
      mysql.replica.sql_delay:
        enabled: true
      mysql.replica.time_behind_source:
        enabled: true
      mysql.statement_event.count:
        enabled: true
      mysql.statement_event.wait.time:
        enabled: true
      mysql.table.average_row_length:
        enabled: true
      mysql.table.lock_wait.read.count:
        enabled: true
      mysql.table.lock_wait.read.time:
        enabled: true
      mysql.table.lock_wait.write.count:
        enabled: true
      mysql.table.lock_wait.write.time:
        enabled: true
      mysql.table.rows:
        enabled: true
      mysql.table.size:
        enabled: true
      mysql.table_open_cache:
        enabled: true

    statement_events: {}

processors:
  resource:
    attributes:
      - key: environment
        value: ${env:ENVIRONMENT}
        action: upsert
      - key: service.name
        value: ${env:SERVICE_NAME}
        action: upsert

  batch:
    timeout: 10s
    send_batch_size: 1024

# Export to base14 Scout
exporters:
  otlphttp/b14:
    endpoint: ${env:OTEL_EXPORTER_OTLP_ENDPOINT}
    tls:
      insecure_skip_verify: true

service:
  pipelines:
    metrics:
      receivers: [mysql]
      processors: [resource, batch]
      exporters: [otlphttp/b14]

allow_native_passwords: true lets the receiver authenticate against MariaDB's native password plugin. Leave the TLS block as shown only for an in-cluster or local stack with TLS disabled; against a TLS-enabled server, configure the CA and drop insecure.

To control metric volume in production, drop the Diagnostic tier with a filter processor while keeping the Core and Operational series.

Environment Variables

.env

MARIADB_HOST=localhost
MYSQL_USER=otel_monitor
MYSQL_PASSWORD=your_password
ENVIRONMENT=your_environment
SERVICE_NAME=your_service_name
OTEL_EXPORTER_OTLP_ENDPOINT=https://<your-tenant>.base14.io

Verify the Setup

Start the Collector and check for metrics within 60 seconds:

# Check Collector logs for scraped MariaDB metrics
docker logs otel-collector 2>&1 | grep -i "mysql"

# Verify MariaDB connectivity and uptime
mariadb -h ${MARIADB_HOST} -P 3306 -u otel_monitor -p \
  -e "SHOW GLOBAL STATUS LIKE 'Uptime';"

-- Thread states (mysql.threads)
SHOW GLOBAL STATUS LIKE 'Threads_%';

-- InnoDB buffer pool (mysql.buffer_pool.*)
SHOW GLOBAL STATUS LIKE 'Innodb_buffer_pool%';

-- Slow queries (mysql.query.slow.count)
SHOW GLOBAL STATUS LIKE 'Slow_queries';

Troubleshooting

Connection refused

Cause: The Collector cannot reach MariaDB at the configured endpoint.

Fix:

1. Verify MariaDB is running: systemctl status mariadb or docker ps | grep mariadb.
2. Confirm the endpoint address and port (default 3306) in your config.
3. Check bind-address in my.cnf - set it to 0.0.0.0 if the Collector runs on a separate host.

Authentication failed

Cause: Monitoring credentials are wrong, or the user lacks grants.

Fix:

1. Test credentials directly: mariadb -h localhost -u otel_monitor -p -e "SELECT 1;".
2. Verify the grants: SHOW GRANTS FOR 'otel_monitor'@'%';.
3. Confirm MYSQL_USER and MYSQL_PASSWORD are set, and that allow_native_passwords: true is present if the server uses native passwords.

Statement-event metrics always zero

Cause: performance_schema is disabled, its statement consumers are off, or the digest tables haven't populated yet.

Look at: the Diagnostic mysql.statement_event.count and mysql.statement_event.wait.time series - both stay flat at zero until performance_schema digests exist.

Fix:

1. Verify it's enabled: SHOW VARIABLES LIKE 'performance_schema';.
2. Check the statement consumers, and enable them if they are off:

SELECT * FROM performance_schema.setup_consumers
WHERE name LIKE 'events_statements%';

UPDATE performance_schema.setup_consumers SET ENABLED = 'YES'
WHERE name LIKE 'events_statements%';

Table-lock-wait metrics stay flat

Cause: No contended table-lock waits have occurred.

Look at: the Diagnostic mysql.table.lock_wait.read.* / .write.* series - they emit only when sessions actually wait on a table lock, so a quiet server reports nothing here. This is expected, not a misconfiguration.

Replica metrics missing

Cause: The server has no replica configured.

Look at: mysql.replica.sql_delay and mysql.replica.time_behind_source - these emit only on a server with an active replication channel.

Fix: No action needed on a standalone server. They surface automatically once replication is configured.

No metrics appearing in Scout

Cause: Metrics are collected but not exported.

Fix:

1. Check Collector logs for export errors: docker logs otel-collector.
2. Verify OTEL_EXPORTER_OTLP_ENDPOINT is set correctly.
3. Confirm the pipeline includes both the receiver and the exporter.

FAQ

Why does this use the MySQL receiver?

MariaDB is wire-compatible with MySQL - both use the MySQL protocol for client connections. The Collector's mysql receiver works against MariaDB without modification. There is no separate MariaDB receiver.

Does this work with MariaDB Galera Cluster?

Yes. Add a receiver block per node with distinct names:

receivers:
  mysql/node1:
    endpoint: node1:3306
    username: ${env:MYSQL_USER}
    password: ${env:MYSQL_PASSWORD}
  mysql/node2:
    endpoint: node2:3306
    username: ${env:MYSQL_USER}
    password: ${env:MYSQL_PASSWORD}

Then include both in the pipeline: receivers: [mysql/node1, mysql/node2].

Does this work with MariaDB running in Kubernetes?

Yes. Set endpoint to the MariaDB service DNS (e.g., mariadb.default.svc.cluster.local:3306) and inject credentials via a Kubernetes secret. The Collector can run as a sidecar or DaemonSet.

What permissions does the monitoring account need?

PROCESS, REPLICATION CLIENT, and SELECT on performance_schema. No write access is required - the Collector only reads metrics.

Where is per-query latency?

The receiver exposes counters and gauges, not per-request timing. mysql.query.slow.count flags queries over long_query_time; for digest breakdowns enable the mysql.statement_event.* metrics, which read performance_schema digests.

Related Guides

• OTel Collector Configuration - Advanced collector configuration.
• Docker Compose Setup - Run the Collector locally.
• Kubernetes Helm Setup - Production deployment.
• Creating Alerts - Alert on MariaDB metrics.
• MySQL Monitoring - The same receiver against MySQL.
• PostgreSQL Monitoring - Alternative relational database.

What's Next?

• Create Dashboards: Explore pre-built dashboards or build your own. See Create Your First Dashboard.
• Monitor More Components: Add monitoring for MySQL, PostgreSQL, and other components.
• Fine-tune Collection: Drop the Diagnostic tier in production with a filter processor to control volume; adjust collection_interval and statement_events limits to your query workload.