vitessio/vitess · critical

failed to parse stop_pos column: %v

Error message

failed to parse stop_pos column: %v

What it means

The stop_pos column stores the position at which the vreplication stream should stop (empty means run indefinitely). replication.DecodePosition failed on its value, meaning the stored stop position is not a decodable GTID set.

Source

Thrown at go/vt/binlog/binlogplayer/binlog_player.go:599

		return VRSettings{}, fmt.Errorf("checkpoint information not available in db for %v", uid)
	}
	vrRow := qr.Named().Row()

	maxTPS, err := vrRow.ToInt64("max_tps")
	if err != nil {
		return VRSettings{}, fmt.Errorf("failed to parse max_tps column: %v", err)
	}
	maxReplicationLag, err := vrRow.ToInt64("max_replication_lag")
	if err != nil {
		return VRSettings{}, fmt.Errorf("failed to parse max_replication_lag column: %v", err)
	}
	startPos, err := DecodePosition(vrRow.AsString("pos", ""))
	if err != nil {
		return VRSettings{}, fmt.Errorf("failed to parse pos column: %v", err)
	}
	stopPos, err := replication.DecodePosition(vrRow.AsString("stop_pos", ""))
	if err != nil {
		return VRSettings{}, fmt.Errorf("failed to parse stop_pos column: %v", err)
	}
	workflowType, err := vrRow.ToInt32("workflow_type")
	if err != nil {
		return VRSettings{}, fmt.Errorf("failed to parse workflow_type column: %v", err)
	}
	workflowSubType, err := vrRow.ToInt32("workflow_sub_type")
	if err != nil {
		return VRSettings{}, fmt.Errorf("failed to parse workflow_sub_type column: %v", err)
	}
	deferSecondaryKeys, err := vrRow.ToBool("defer_secondary_keys")
	if err != nil {
		return VRSettings{}, fmt.Errorf("failed to parse defer_secondary_keys column: %v", err)
	}
	options := vrRow.AsString("options", "{}")
	var workflowOptions vtctldata.WorkflowOptions
	if err := json.Unmarshal([]byte(options), &workflowOptions); err != nil {
		return VRSettings{}, fmt.Errorf("failed to parse options column: %v", err)
	}

View on GitHub (pinned to 01a25a7d17)

Solutions

1. Inspect: `select uid, stop_pos from _vt.vreplication where uid=<id>`.
2. Fix or clear it: `update _vt.vreplication set stop_pos='' where uid=<id>` to run without a stop point, or set a valid encoded GTID set.
3. If a stop point is required, capture it properly from the source (`SELECT @@global.gtid_executed`) and encode with the same flavor.
4. Prefer workflow-level commands (e.g. MoveTables complete) over hand-editing stop_pos.

Example fix

// before: malformed stop point
update _vt.vreplication set stop_pos='1-5' where uid=1;
// after: valid GTID set or empty to disable
update _vt.vreplication set stop_pos='' where uid=1;

qr, _ := dbClient.ExecuteFetch(fmt.Sprintf("SELECT stop_pos FROM _vt.vreplication WHERE uid=%d", uid), 1)
if len(qr.Rows) == 1 {
	sp := qr.Named().Row().AsString("stop_pos", "")
	if sp != "" {
		if _, err := replication.DecodePosition(sp); err != nil {
			return fmt.Errorf("stop_pos %q invalid; clear it or set a valid GTID set", sp)
		}
	}
}

func isValidStopPos(sp string) bool {
	if sp == "" { return true } // empty means run indefinitely
	_, err := replication.DecodePosition(sp)
	return err == nil
}

settings, err := binlogplayer.ReadVRSettings(dbClient, uid)
if err != nil && strings.Contains(err.Error(), "failed to parse stop_pos") {
	_, _ = dbClient.ExecuteFetch(fmt.Sprintf("UPDATE _vt.vreplication SET stop_pos='' WHERE uid=%d", uid), 0)
	settings, err = binlogplayer.ReadVRSettings(dbClient, uid)
}

When it happens

Trigger: DecodePosition on stop_pos fails: manually entered stop position in the wrong format, flavor mismatch (MariaDB vs MySQL GTID), truncated value, or a stray non-empty invalid string left after workflow edits.

Common situations: Users setting a stop point via direct SQL instead of the workflow API; cross-flavor restore; copy-paste of a position with a typo.

Understand the failure class

• Parsing and encoding errors: unexpected token, malformed input — why parsers reject input and how to find the real culprit.

Related errors

• failed to parse pos column: %v
• failed to parse max_tps column: %v
• failed to parse max_replication_lag column: %v
• failed to parse options column: %v
• empty gtid passed to setPosition

AI-assisted analysis of vitessio/vitess@01a25a7d17 (2026-09-01). Data as JSON: /api/errors/5a532aa46cbc8f6a. Report an issue: GitHub.