vitessio/vitess · error

can't parse INTVAR_EVENT

Error message

can't parse INTVAR_EVENT: %v, event data: %#v

What it means

INTVAR_EVENTs carry SET statements for internal variables (LAST_INSERT_ID, INSERT_ID). parseEvents decodes them with ev.IntVar(format); a failure means the event body doesn't match the expected intvar layout, so the equivalent SET statement cannot be reconstructed and the stream aborts.

Solutions

1. Run mysqlbinlog on the affected binlog file to check for corruption
2. Restore a healthy binlog source (fail over to a replica with intact logs) and restart the stream from the last good GTID
3. Check disk/filesystem health on the primary producing these binlogs
4. Bypass any proxies or intermediaries that may truncate binlog dump packets

if err := streamer.Stream(ctx); err != nil {
	if strings.Contains(err.Error(), "INTVAR_EVENT") {
		// corrupt intvar event: verify with mysqlbinlog, fail over, restart from last good GTID
	}
}

When it happens

Trigger: During Stream/parseEvents, ev.IsIntVar() is true and ev.IntVar(format) errors because the event body is shorter than 9 bytes or otherwise malformed relative to the format's header size.

Common situations: Binlog files corrupted or truncated mid-event; replication through a proxy that drops bytes; binlog written by an unusual server build; disk issues on the primary.

Related errors

• can't parse binlog event, invalid data: %#v
• can't get GTID from binlog event
• can't parse binlog event: invalid data: %#v
• can't parse FORMAT_DESCRIPTION_EVENT
• can't strip checksum from binlog event

AI-assisted analysis of vitessio/vitess@01a25a7d17 (2026-09-01). Data as JSON: /api/errors/c68c872ef4912fc9. Report an issue: GitHub.

Appendix: source

Thrown at go/vt/binlog/binlog_streamer.go:379

			}
		case ev.IsGTID(): // GTID_EVENT: update current GTID, maybe BEGIN.
			var hasBegin bool
			gtid, hasBegin, _, _, err = ev.GTID(format)
			if err != nil {
				return pos, fmt.Errorf("can't get GTID from binlog event: %v, event data: %#v", err, ev)
			}
			pos = replication.AppendGTID(pos, gtid)
			if hasBegin {
				begin()
			}
		case ev.IsXID(): // XID_EVENT (equivalent to COMMIT)
			if err = commit(ev.Timestamp()); err != nil {
				return pos, err
			}
		case ev.IsIntVar(): // INTVAR_EVENT
			typ, value, err := ev.IntVar(format)
			if err != nil {
				return pos, fmt.Errorf("can't parse INTVAR_EVENT: %v, event data: %#v", err, ev)
			}
			statements = append(statements, FullBinlogStatement{
				Statement: &binlogdatapb.BinlogTransaction_Statement{
					Category: binlogdatapb.BinlogTransaction_Statement_BL_SET,
					Sql:      fmt.Appendf(nil, "SET %s=%d", mysql.IntVarNames[typ], value),
				},
			})
		case ev.IsRand(): // RAND_EVENT
			seed1, seed2, err := ev.Rand(format)
			if err != nil {
				return pos, fmt.Errorf("can't parse RAND_EVENT: %v, event data: %#v", err, ev)
			}
			statements = append(statements, FullBinlogStatement{
				Statement: &binlogdatapb.BinlogTransaction_Statement{
					Category: binlogdatapb.BinlogTransaction_Statement_BL_SET,
					Sql:      fmt.Appendf(nil, "SET @@RAND_SEED1=%d, @@RAND_SEED2=%d", seed1, seed2),
				},
			})

View on GitHub (pinned to 01a25a7d17)