# Percona MySQL 8.0.25-15 | \[ERROR\] \[MY-011087\] \[Server\] Different lower\_case\_table\_names settings for server ('1') and data dictionary ('0') & \[ERROR\] \[MY-010020\] \[Server\] Data Dictionary initialization failed. | lower-case-table-names = 1

**URL:** <https://forums.percona.com/t/percona-mysql-8-0-25-15-error-my-011087-server-different-lower-case-table-names-settings-for-server-1-and-data-dictionary-0-error-my-010020-server-data-dictionary-initialization-failed-lower-case-table-names-1/12054>\
**Category:** Percona Server for MySQL 8.0\
**Tags:** mysql, percona\
**Created:** [September 6, 2021, 1:37pm UTC](https://forums.percona.com/t/percona-mysql-8-0-25-15-error-my-011087-server-different-lower-case-table-names-settings-for-server-1-and-data-dictionary-0-error-my-010020-server-data-dictionary-initialization-failed-lower-case-table-names-1/12054 "2021-09-06T13:37:20Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![AneeshBabu](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/aneeshbabu/32/1393_2.png) [@AneeshBabu](https://forums.percona.com/u/AneeshBabu)\
**Post date:** [September 6, 2021, 1:37pm UTC](https://forums.percona.com/t/percona-mysql-8-0-25-15-error-my-011087-server-different-lower-case-table-names-settings-for-server-1-and-data-dictionary-0-error-my-010020-server-data-dictionary-initialization-failed-lower-case-table-names-1/12054/1 "2021-09-06T13:37:20Z")

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Hi there,  
When starting `MySQL8.0.25-15` with the parameter `lower-case-table-names = 1` in the config file,Below is the error faced.  
How to start `MySQL` …?

```auto

2021-09-06T18:43:13.945448+05:30 0 [System] [MY-010116] [Server] /usr/sbin/mysqld (mysqld 8.0.25-15) starting as process 22086
2021-09-06T18:43:13.953842+05:30 1 [System] [MY-013576] [InnoDB] InnoDB initialization has started.
2021-09-06T18:43:22.218936+05:30 1 [System] [MY-013577] [InnoDB] InnoDB initialization has ended.
2021-09-06T18:43:22.230577+05:30 1 [ERROR] [MY-011087] [Server] Different lower_case_table_names settings for server ('1') and data dictionary ('0') .
2021-09-06T18:43:22.231016+05:30 0 [ERROR] [MY-010020] [Server] Data Dictionary initialization failed.
2021-09-06T18:43:22.231515+05:30 0 [ERROR] [MY-010119] [Server] Aborting
2021-09-06T18:43:23.483201+05:30 0 [System] [MY-010910] [Server] /usr/sbin/mysqld: Shutdown complete (mysqld 8.0.25-15) Percona Server (GPL), Relea se 15, Revision a558ec2.

```

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<div class="post-metadata">

**Author:** ![jrivera](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/jrivera/32/13_2.png) [@jrivera](https://forums.percona.com/u/jrivera)\
**Post date:** [September 7, 2021, 2:04am UTC](https://forums.percona.com/t/percona-mysql-8-0-25-15-error-my-011087-server-different-lower-case-table-names-settings-for-server-1-and-data-dictionary-0-error-my-010020-server-data-dictionary-initialization-failed-lower-case-table-names-1/12054/2 "2021-09-07T02:04:19Z")

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> [@AneeshBabu](#):
>
> `Different lower_case_table_names settings for server`

Based on documentation it is prohibited to start the server with lower\_case\_table\_names different from the value when the data directory was initialized. If you need to change lower\_case\_table\_names to 1 from 0 you’ll need to reinitialize the data directory but prior to that you will want to backup the data prior to re-initializing the data directory.  
Reference: [https://dev.mysql.com/doc/refman/8.0/en/server-system-variables.html#sysvar\_lower\_case\_table\_names](https://dev.mysql.com/doc/refman/8.0/en/server-system-variables.html#sysvar_lower_case_table_names)