What causes "failed to get position after clone: %v" in vitessio/vitess?

Check mysqld is up and accepting connections on the expected socket/port after clone.

failed to get position after clone: %v

Error message

failed to get position after clone: %v

What it means

After a successful CLONE, CloneFromDonor queries mysqld.PrimaryPosition to learn the cloned position; if the query fails within the post-clone timeout (clonePrimaryPositionTimeout), the restore aborts because the position is required to configure replication.

Source

Thrown at go/vt/mysqlctl/clone.go:140

		UseSSL:        cloneConfig.UseSSL,
	}

	log.Info(fmt.Sprintf("Clone executor configured for donor %s:%d", executor.DonorHost, executor.DonorPort))

	// Execute the clone operation.
	// Note: ExecuteClone will wait for mysqld to restart and for the CLONE plugin to report successful completion
	// success via performance_schema before returning.
	if err := executor.ExecuteClone(ctx, mysqld, mycnf, cloneRestartWaitTimeout); err != nil {
		return replication.Position{}, fmt.Errorf("clone execution failed: %v", err)
	}

	// After CLONE, keep going across the expected mysqld restart.
	ctx, cancel := context.WithTimeout(ctx, clonePrimaryPositionTimeout)
	defer cancel()

	pos, err := mysqld.PrimaryPosition(ctx)
	if err != nil {
		return replication.Position{}, fmt.Errorf("failed to get position after clone: %v", err)
	}

	log.Info(fmt.Sprintf("Clone completed successfully at position %v", pos))
	return pos, nil
}

// CloneExecutor handles MySQL CLONE REMOTE operations for backup and replica provisioning.
// It executes CLONE INSTANCE FROM on the recipient to clone data from a donor.
type CloneExecutor struct {
	// DonorHost is the hostname or IP of the donor MySQL instance.
	DonorHost string
	// DonorPort is the MySQL port of the donor instance.
	DonorPort int
	// DonorUser is the MySQL user for clone operations (needs BACKUP_ADMIN on donor).
	DonorUser string
	// DonorPassword is the password for the clone user.
	DonorPassword string
	// UseSSL indicates whether to use SSL for the clone connection.

View on GitHub (pinned to 01a25a7d17)

Solutions

Check mysqld is up and accepting connections on the expected socket/port after clone.
Inspect mysqld error log for slow InnoDB recovery; increase clonePrimaryPositionTimeout if restarts are slow.
Retry the restore; the clone may have completed but restart raced the query.
Verify dbconfigs/socket settings still match the restarted mysqld.

Defensive patterns

Strategy: retry

Validate before calling

// ensure mysqld is accepting connections before querying position
if err := mysqld.Ping(ctx); err != nil {
	// wait/retry until mysqld is back up
}

Try / catch

if err != nil && strings.Contains(err.Error(), "failed to get position after clone") {
	// wait for mysqld restart to finish, then retry the restore
}

Prevention

Allow generous post-clone timeouts for large datasets
Watch mysqld error log during InnoDB recovery
Confirm socket/port config survives the clone restart

When it happens

Trigger: mysqld not fully restarted after CLONE, MySQL connection unavailable (wrong socket/port after restart), performance_schema not readable, or timeout too short for slow restarts.

Common situations: Slow mysqld startup after cloning a large dataset, mysqld restart racing the position query, socket path changed by the cloned my.cnf, MySQL refusing connections during InnoDB recovery.

Related errors

AI-assisted analysis of vitessio/vitess@01a25a7d17 (2026-09-01). Data as JSON: /api/errors/823a20de6b1f00d4. Report an issue: GitHub.