Merge pull request #8340 from planetscale/fix-8315-release-9

workaround xtrabackup error using mysql global variable old_alter_table

go/test/endtoend/recovery/unshardedrecovery/recovery.go

@@ -100,6 +100,11 @@ func TestMainImpl(m *testing.M) {
  sql := string(initDb)
  newInitDBFile = path.Join(localCluster.TmpDirectory, "init_db_with_passwords.sql")
  sql = sql + initialsharding.GetPasswordUpdateSQL(localCluster)
+ // https://github.com/vitessio/vitess/issues/8315
+ oldAlterTableMode := `
+SET GLOBAL old_alter_table = ON;
+`
+ sql = sql + oldAlterTableMode
  ioutil.WriteFile(newInitDBFile, []byte(sql), 0666)
 
  extraArgs := []string{"-db-credentials-file", dbCredentialFile}

go/vt/mysqlctl/xtrabackupengine.go

@@ -299,6 +299,7 @@ func (be *XtrabackupEngine) backupFiles(ctx context.Context, params BackupParams
  // the replication position. Note that if we don't read stderr as we go, the
  // xtrabackup process gets blocked when the write buffer fills up.
  stderrBuilder := &strings.Builder{}
+ posBuilder := &strings.Builder{}
  stderrDone := make(chan struct{})
  go func() {
  defer close(stderrDone)
@@ -318,7 +319,7 @@ func (be *XtrabackupEngine) backupFiles(ctx context.Context, params BackupParams
  }
  capture = true
  }
- fmt.Fprintln(stderrBuilder, line)
+ fmt.Fprintln(posBuilder, line)
  }
  if err := scanner.Err(); err != nil {
  params.Logger.Errorf("error reading from xtrabackup stderr: %v", err)
@@ -359,10 +360,11 @@ func (be *XtrabackupEngine) backupFiles(ctx context.Context, params BackupParams
  sterrOutput := stderrBuilder.String()
 
  if err := backupCmd.Wait(); err != nil {
- return replicationPosition, vterrors.Wrap(err, "xtrabackup failed with error")
+ return replicationPosition, vterrors.Wrap(err, fmt.Sprintf("xtrabackup failed with error. Output=%s", sterrOutput))
  }
 
- replicationPosition, rerr := findReplicationPosition(sterrOutput, flavor, params.Logger)
+ posOutput := posBuilder.String()
+ replicationPosition, rerr := findReplicationPosition(posOutput, flavor, params.Logger)
  if rerr != nil {
  return replicationPosition, vterrors.Wrap(rerr, "backup failed trying to find replication position")
  }