Hi there. I'm going through an upgrade process I have done before with earlier versions of mariaDB and Mysql, but running into an issue. My goal is to create a new slave including upgrade process from MariaDB 10.2.22 (serverOld) to 10.5.12 on a new server (serverNew) (as inspired by the brighter mind at https://www.stephenrlang.com/2016/08/setting-up-mysql-master-slave-replicati... ) 1. rsync /var/lib/mysql from serverOld to serverNew 2. On serverOld: FLUSH TABLES WITH READ LOCK; SHOW MASTER STATUS; 3. rerun rsync from serverOld to serverNew 4. Release read lock from serverOld 5. Start mariadb on serverNew 6. run mysql_upgrade on serverNew 7. Celebrate and have a nap In actual practice step #5 failed numerous times before what I think is now an okay serverNew # Innodb settings between serverOld and serverNew #serverOld innodb-flush-method = O_DIRECT innodb-log-files-in-group = 2 innodb-log-file-size = 48M innodb-flush-log-at-trx-commit = 2 innodb-file-per-table = 1 innodb-buffer-pool-size = 128M #serverNew innodb-flush-method = O_DIRECT innodb-log-file-size = 48M innodb-flush-log-at-trx-commit = 2 innodb-file-per-table = 1 innodb-buffer-pool-size = 128M The only difference is innodb-log-files-in-group setting is removed in serverNew, as it has been depricated and removed in 10.5 # Upgrade after crash? When attempting to start serverNew, it would fail with the following error: [ERROR] InnoDB: Upgrade after a crash is not supported. The redo log was created with MariaDB 10.2.22. [ERROR] InnoDB: Plugin initialization aborted with error Generic error the log file on serverOld showed no evidence of crashing. None the less, I restarted serverOld, and reran the process above. Still the same issue step #5. # Remove ib_logfile* files I then tried forcing the recreation of the redo logs by removing them and then starting up serverNew. This resulted in the following scary errors: [ERROR] InnoDB: Page [page id: space=0, page number=1984] log sequence number 285722576186 is in the future! Current system log sequence number 259573448177. [ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to https://mariadb.com/kb/en/library/innodb-recovery-modes/ for information about forcing recovery. # innodb_fast_shutdown = 0 The next attempt started with serverOld being restarted and innodb_fast_shutdown = 0 being set beforehand. I reran the above steps and still got stuck on step #5 with the following error: [ERROR] InnoDB: Upgrade after a crash is not supported. The redo log was created with MariaDB 10.2.22. [ERROR] InnoDB: Plugin initialization aborted with error Generic error This time, however, when I removed the ib_logfile* files, we seemed to have an okay startup: [Note] InnoDB: Initializing buffer pool, total size = 134217728, chunk size = 134217728 [Note] InnoDB: Completed initialization of buffer pool [Note] InnoDB: Setting log file ./ib_logfile101 size to 50331648 bytes [Note] InnoDB: Renaming log file ./ib_logfile101 to ./ib_logfile0 [Note] InnoDB: New log file created, LSN=288830457728 [Note] InnoDB: 128 rollback segments are active. [Note] InnoDB: Removed temporary tablespace data file: "ibtmp1" [Note] InnoDB: Creating shared tablespace for temporary tables [Note] InnoDB: Setting file './ibtmp1' size to 12 MB. Physically writing the file full; Please wait ... [Note] InnoDB: File './ibtmp1' size is now 12 MB. [Note] InnoDB: 10.5.12 started; log sequence number 0; transaction id 3037161218 [Note] Plugin 'FEEDBACK' is disabled. [Note] Recovering after a crash using /var/lib/mysql/mysql-bin [Note] Starting crash recovery... [Note] Crash recovery finished. [Note] InnoDB: Loading buffer pool(s) from /var/lib/mysql/ib_buffer_pool [Note] Server socket created on IP: '::'. [ERROR] Incorrect definition of table mysql.event: expected column 'sql_mode' at position 14 to have type set('REAL_AS_FLOAT','PIPES_AS_CONCAT','ANSI_QUOTES','IGNORE_SPACE','IGNORE_BAD_TABLE_OPTIONS','ONLY_FULL_GROUP_BY','NO_UNSIGNED_SUBTRACTION','NO_DIR_IN_CREATE','POSTGRESQL','ORACLE','MSSQL','DB2','MAXDB','NO_KEY_OPTIONS','NO_TABLE_OPTIONS','NO_FIELD_OPTIONS','MYSQL323','MYSQL40','ANSI','NO_AUTO_VALUE_ON_ZERO','NO_BACKSLASH_ESCAPES','STRICT_TRANS_TABLES','STRICT_ALL_TABLES','NO_ZERO_IN_DATE','NO_ZERO_DATE','INVALID_DATES','ERROR_FOR_DIVISION_BY_ZERO','TRADITIONAL','NO_AUTO_CREATE_USER','HIGH_NOT_PRECEDENCE','NO_ENGINE_SUBSTITUTION','PAD_CHAR_TO_FULL_LENGTH','EMPTY_STRING_IS_NULL','SIMULTANEOUS_ASSIGNMENT'), found type set('REAL_AS_FLOAT','PIPES_AS_CONCAT','ANSI_QUOTES','IGNORE_SPACE','IGNORE_BAD_TABLE_OPTIONS','ONLY_FULL_GROUP_BY','NO_UNSIGNED_SUBTRACTION','NO_DIR_IN_CREATE','POSTGRESQL','ORACLE','MSSQL','DB2','MAXDB','NO_KEY_OPTIONS','NO_TABLE_OPTIONS','NO_FIELD_OPTIONS','MYSQL323','MYSQL40','ANSI','NO_AUTO_VALU [ERROR] mariadbd: Event Scheduler: An error occurred when initializing system tables. Disabling the Event Scheduler. [Note] Reading of all Master_info entries succeeded [Note] Added new Master_info '' to hash table [Note] /usr/sbin/mariadbd: ready for connections. Version: '10.5.12-MariaDB-1:10.5.12+maria~focal-log' socket: '/run/mysqld/mysqld.sock' port: 3306 mariadb.org binary distribution Running mysql_upgrade completed without issue. I'm not feeling confident that this upgrade is actually okay. removing the ib_logfile* seems questionable as a requirement to get the upgrade done. Anyone have similar troubles? Recommendations on what my process should be? Thanks, Mike