Alerter Configuration

The pgEdge AI DBA Workbench Alerter supports configuration through YAML files and command-line flags. The alerter applies configuration settings in the following order; later sources override earlier ones:

1. Default values built into the application.
2. Configuration file settings (YAML format).
3. Command-line flag overrides.

The alerter searches for its configuration file in the following order:

1. The path specified via the -config flag.
2. The per-user config directory at ~/.config/pgedge/ai-dba-alerter.yaml on Linux (honouring $XDG_CONFIG_HOME), ~/Library/Application Support/pgedge/ai-dba-alerter.yaml on macOS, and %AppData%\pgedge\ai-dba-alerter.yaml on Windows.
3. /etc/pgedge/ai-dba-alerter.yaml (system-wide).

If -config is set and the file is missing, the alerter exits with an error. If -config is not set and none of the default locations contain a configuration file, the alerter uses built-in defaults silently. The alerter no longer searches the binary directory or the current working directory. A SIGHUP signal re-runs discovery on each reload, so a configuration file installed at a default location after startup is picked up on the next signal.

A complete sample configuration file is available at ai-dba-alerter.yaml in the project repository.

Reloading or Restarting the Alerter

The alerter responds to Unix signals for operational control:

• SIGINT and SIGTERM trigger a graceful shutdown.
• SIGHUP reloads the configuration file without restarting the process.

In the following example, the kill command reloads the configuration:

kill -HUP $(pidof ai-dba-alerter)

Security Best Practices

Store API keys for LLM providers in files with restricted permissions. The alerter reads API keys from the paths specified in the api_key_file options.

In the following example, the commands create an API key file with secure permissions:

echo "sk-your-api-key-here" \
    > /etc/ai-workbench/openai-api-key.txt
chmod 600 /etc/ai-workbench/openai-api-key.txt

The corresponding configuration then references the key file:

llm:
  embedding_provider: openai
  reasoning_provider: openai
  openai:
    api_key_file: /etc/ai-workbench/openai-api-key.txt
    embedding_model: text-embedding-3-small
    reasoning_model: gpt-4o

For additional security in a production deployment, always use SSL with certificate verification. In the following example, the datastore section configures a secure connection with certificate verification:

datastore:
  host: db.example.com
  database: ai_workbench
  username: ai_workbench
  password_file: /etc/ai-workbench/password.txt
  port: 5432
  sslmode: verify-full
  sslcert: /etc/ai-workbench/client-cert.pem
  sslkey: /etc/ai-workbench/client-key.pem
  sslrootcert: /etc/ai-workbench/ca-cert.pem

Configuration File Reference

The configuration file uses YAML format. For details about the available Alerter configuration options, see:

• Datastore Connection (datastore)
• Connection Pool (pool)
• Threshold Evaluation (threshold)
• Anomaly Detection (anomaly)
  • Tier 1: Statistical Analysis
  • Tier 1: Variance Floor, Warmup, and Z-Score Cap
  • Tier 2: Embedding Similarity
  • Tier 3: LLM Classification
• Baseline Calculation (baselines)
• Correlation (correlation)
• LLM Providers (llm)
  • Ollama Configuration
  • OpenAI Configuration
  • Anthropic Configuration
  • Gemini Configuration
  • Voyage Configuration
• Notifications (notifications)

Datastore Connection (datastore)

The datastore section configures the connection to the AI DBA Workbench PostgreSQL datastore.

The sslmode option accepts the following values:

• disable disables SSL encryption.
• allow attempts non-SSL first and falls back to SSL.
• prefer attempts SSL first and falls back to non-SSL.
• require requires SSL without certificate verification.
• verify-ca requires SSL and verifies the server certificate.
• verify-full requires SSL and verifies the certificate and hostname.

Connection Pool (pool)

The pool section configures the database connection pool.

Threshold Evaluation (threshold)

The threshold section configures threshold-based alert evaluation.

Anomaly Detection (anomaly)

The anomaly section configures the tiered anomaly detection system.

Tier 1: Statistical Analysis

The anomaly.tier1 section configures z-score-based statistical detection.

Tier 1: Variance Floor, Warmup, and Z-Score Cap

Three additional blocks under anomaly.tier1 prevent the detector from firing on baselines that have not yet stabilised. These blocks are most relevant on young datastores; on a datastore with one or two days of metric history, a baseline's stored standard deviation can collapse far below the metric's natural variation, producing z-scores in the thousands. The variance floor and warmup gate suppress this failure mode, and the z-score cap acts as defence in depth.

The anomaly.tier1.max_z_score option clamps the absolute z-score symmetrically around zero before the sensitivity comparison. The default is 100.0; any genuine outlier sits well below this value, and the cap simply prevents a runaway divisor from generating multi-thousand-sigma scores. Setting max_z_score: 0 disables the cap.

The anomaly.tier1.variance_floor block enforces a minimum divisor on the z-score calculation. The effective standard deviation is the larger of the raw stored value and a hybrid floor; the floor itself is the larger of relative_pct times the absolute baseline mean and absolute_floor. The relative term dominates for non-zero metrics, while the absolute term acts as a safety net when the mean approaches zero. Setting both relative_pct: 0 and absolute_floor: 0 disables the floor entirely; the detector then falls back to the existing stddev == 0 guard.

The anomaly.tier1.warmup block suppresses detection for baselines that have not accumulated enough samples or enough wall-clock observation time. Each period_type (all, hourly, and daily) has its own pair of thresholds, and a baseline is considered warm only when both are met. The all baseline defaults require roughly one day of operation at the 60 second collection interval; the hourly and daily defaults require enough span for each time bucket to have been observed multiple times. Setting both min_samples: 0 and min_span_hours: 0 for a given period_type disables warmup suppression for that type.

In the following example, the anomaly.tier1 section tightens the variance floor and extends the all warmup window:

anomaly:
  tier1:
    max_z_score: 100.0
    variance_floor:
      relative_pct: 0.10
      absolute_floor: 0.005
    warmup:
      all:
        min_samples: 200
        min_span_hours: 48
      hourly:
        min_samples: 5
        min_span_hours: 120
      daily:
        min_samples: 3
        min_span_hours: 336

Warmup suppressions are recorded at debug log level only; the detector does not write a candidate row or an alert when it skips a cold baseline. On the long-term test host, enable debug logging in the alerter and inspect recent suppressions with sudo journalctl -u ai-workbench-alerter.service --since 10m. The log line names the connection, metric, period type, and sample count, which is enough to confirm whether a missing alert reflects warmup suppression or a genuinely quiet metric.

Tier 2: Embedding Similarity

The anomaly.tier2 section configures pgvector-based similarity search for pattern matching.

Tier 3: LLM Classification

The anomaly.tier3 section configures LLM-based classification for complex anomalies.

Baseline Calculation (baselines)

The baselines section configures baseline metric calculation for anomaly detection.

Correlation (correlation)

The correlation section configures alert correlation across metrics.

LLM Providers (llm)

The llm section configures LLM providers for tier 3 anomaly detection and embedding generation.

Ollama Configuration

The llm.ollama section configures the local Ollama provider.

OpenAI Configuration

The llm.openai section configures the OpenAI provider.

The openai provider works with any server that implements the OpenAI-compatible API. Set base_url to point at a local inference server. The API key is optional when using a custom base URL.

The following local inference servers are compatible:

• Docker Model Runner uses http://localhost:12434/engines/llama.cpp/v1 as the default endpoint.
• llama.cpp uses http://localhost:8080/v1 as the default endpoint.
• LM Studio uses http://localhost:1234/v1 as the default endpoint.
• EXO uses http://localhost:52415/v1 as the default endpoint.

In the following example, the llm.openai section configures a local llama.cpp server:

llm:
  reasoning_provider: openai
  openai:
    base_url: http://localhost:8080/v1
    reasoning_model: my-local-model

Anthropic Configuration

The llm.anthropic section configures the Anthropic provider.

Gemini Configuration

The llm.gemini section configures the Google Gemini provider. Model availability varies by Gemini API key tier; run ListModels to verify which models a given key can access.

When Gemini is the embedding provider, the embedding_model must match the model that the KB Builder used to produce the knowledgebase; the KB Builder uses gemini-embedding-001.

Voyage Configuration

The llm.voyage section configures the Voyage provider for embeddings.

Notifications (notifications)

The notifications section configures the notification delivery system for sending alerts through external channels.

The secret_file option specifies a file containing the same plain text secret used by the server component. The alerter uses this secret to decrypt notification channel credentials that the server encrypted. The alerter and the server must reference the same secret file.

In the following example, the notifications section enables delivery with custom retry settings:

notifications:
  enabled: true
  secret_file: /etc/ai-workbench/ai-dba-server.secret
  process_interval_seconds: 30
  max_retry_attempts: 5
  retry_backoff_minutes: [5, 15, 30]
  http_timeout_seconds: 60

Command-Line Flags

After applying default values and command-line flags, the server applies command-line flags to fill in any remaining settings. The alerter accepts the following command-line flags:

In the following example, the alerter starts with debug logging and a custom configuration file:

./ai-dba-alerter -debug \
    -config /etc/ai-workbench/alerter.yaml

In the following example, the alerter connects to a specific database without a configuration file:

./ai-dba-alerter \
    -db-host db.example.com \
    -db-name ai_workbench \
    -db-user alerter \
    -db-password secret