multica-ai/multica · critical

ping database: %w

Error message

ping database: %w

What it means

Returned when the pool was created but pool.Ping(ctx) fails — the tool's first actual round-trip to postgres. It means the DSN parsed and the pool object exists, but the server rejected or never answered the connection: wrong credentials, database does not exist, pg_hba rejection, TLS failure, or network drop. Distinguish it from 'connect to database', which is a DSN/pool-construction failure.

Source

Thrown at server/cmd/backfill_codex_usage_cache/main.go:96

		return err
	}

	dbURL := os.Getenv("DATABASE_URL")
	if dbURL == "" {
		dbURL = "postgres://multica:multica@localhost:5432/multica?sslmode=disable"
	}

	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
	defer stop()

	pool, err := pgxpool.New(ctx, dbURL)
	if err != nil {
		return fmt.Errorf("connect to database: %w", err)
	}
	defer pool.Close()

	if err := pool.Ping(ctx); err != nil {
		return fmt.Errorf("ping database: %w", err)
	}

	rows, total, err := loadDryRunSummary(ctx, pool, cfg)
	if err != nil {
		return err
	}
	logSummary(cfg, rows, total)
	if total.Rows == 0 {
		slog.Info("no eligible Codex task_usage rows found")
		return nil
	}
	if !cfg.execute {
		slog.Info("dry-run complete; review the summary, then re-run with --execute to apply the backfill")
		return nil
	}

	lockConn, err := pool.Acquire(ctx)
	if err != nil {

View on GitHub (pinned to 2c0912b6ec)

Solutions

1. Confirm credentials and database name in DATABASE_URL by connecting with psql using the same DSN.
2. Match sslmode to the server (try sslmode=require for managed postgres).
3. If pg_hba rejects the client, run the tool from an allowed host or have the DBA allow it.
4. Re-run — transient network blips between pool creation and ping are possible.

Example fix

# before
export DATABASE_URL='postgres://multica:multica@localhost:5432/multica?sslmode=disable'
./backfill_codex_usage_cache --cutoff ...  # ping database: ... (auth failed / no ssl)

# after
export DATABASE_URL='postgres://multica:multica@db.internal:5432/multica?sslmode=require'
./backfill_codex_usage_cache --cutoff 2026-01-01T00:00:00Z

# Pre-flight the exact DSN, including TLS mode
PGCONNECT_TIMEOUT=5 psql "$DATABASE_URL" -c 'select 1' || echo 'fix DSN: credentials, dbname, or sslmode'

When it happens

Trigger: Valid-format DSN with wrong password/user (auth failure), non-existent database name, pg_hba.conf denying the client IP, server requiring TLS the client didn't negotiate, or a firewall dropping the connection after DNS resolution.

Common situations: Credentials rotated after the DSN was written; pointing at the right host but the wrong database name; running the backfill from CI/NAT whose IP is not in pg_hba; managed postgres enforcing SSL while sslmode=disable.

Related errors

• connect to database: %w
• acquire advisory lock %d: %w
• rebuild hourly rollup for update window %s..%s: %w
• acquire advisory-lock connection: %w
• load dry-run summary: %w

AI-assisted analysis of multica-ai/multica@2c0912b6ec (2026-08-15). Data as JSON: /api/errors/eaf6fa2013cdac21. Report an issue: GitHub.