mysqldump: Error 2020: Got packet bigger than 'max_allowed_packet' bytes

導出資料庫時，報以下錯誤：

mysqldump: Error 2020: Got packet bigger than 'max_allowed_packet' bytes when dumping table `ib_mailbox_backup` at row: 3369

解決辦法：

You can add --max_allowed_packet=512M to your mysqldump command.

Or add max_allowed_packet=512M to [mysqldump] section of your my.cnf