Downgrade Persona 5.6 to 5.5 failed

MySQL & MariaDB Other MySQL® Questions
1

Hello to everyone !
Due to some reasons (Handlersocket for Percona 5.6 is not implemented and no any information when it will happen) I’ve tried to downgrade from Percona 5.6 to Percona 5.5 - IT FAILED.
Step-by step downgrade

Step 1)
service mysql stop // OK

Step 2)
[root@falcon238]# rpm -qa | grep Percona-Server
Percona-Server-shared-compat-5.5.35-rel33.0.611.rhel6.x86_64
Percona-Server-shared-56-5.6.15-rel63.0.519.rhel6.x86_64
Percona-Server-server-56-5.6.15-rel63.0.519.rhel6.x86_64
Percona-Server-devel-56-5.6.15-rel63.0.519.rhel6.x86_64
Percona-Server-client-56-5.6.15-rel63.0.519.rhel6.x86_64

Step 3)
rpm -qa | grep Percona-Server | xargs rpm -e --nodeps // OK

Step 4)
yum install Percona-Server-server-55 Percona-Server-client-55 Percona-Server-shared-55 Percona-Server-devel-55 Percona-Server-shared-compat percona-toolkit xtrabackup perl-DBD-MySQL php-mysql MySQL-python
** Found 3 pre-existing rpmdb problem(s), ‘yum check’ output follows: //not too good…
percona-xtrabackup-20-2.0.8-587.rhel6.x86_64 has missing requires of /usr/bin/mysql
perl-DBD-MySQL-4.022-1.el6.rfx.x86_64 has missing requires of mysql
2 : postfix-2.6.6-6.el6_5.x86_64 has missing requires of mysql-libs
Installing : Percona-Server-shared-55-5.5.35-rel33.0.611.rhel6.x86_64 1/5
Installing : Percona-Server-client-55-5.5.35-rel33.0.611.rhel6.x86_64 2/5
Installing : Percona-Server-server-55-5.5.35-rel33.0.611.rhel6.x86_64 3/5
Percona Server is distributed with several useful UDF (User Defined Function) from Maatkit.
Run the following commands to create these functions:
mysql -e “CREATE FUNCTION fnv1a_64 RETURNS INTEGER SONAME ‘libfnv1a_udf.so’”
mysql -e “CREATE FUNCTION fnv_64 RETURNS INTEGER SONAME ‘libfnv_udf.so’”
mysql -e “CREATE FUNCTION murmur_hash RETURNS INTEGER SONAME ‘libmurmur_udf.so’”
See [URL=“Google Code Archive - Long-term storage for Google Code Project Hosting.”]Google Code Archive - Long-term storage for Google Code Project Hosting. for more details
Installing : Percona-Server-devel-55-5.5.35-rel33.0.611.rhel6.x86_64 4/5
Installing : Percona-Server-shared-compat-5.5.35-rel33.0.611.rhel6.x86_64 5/5
Verifying : Percona-Server-server-55-5.5.35-rel33.0.611.rhel6.x86_64 1/5
Verifying : Percona-Server-shared-55-5.5.35-rel33.0.611.rhel6.x86_64 2/5
Verifying : Percona-Server-shared-compat-5.5.35-rel33.0.611.rhel6.x86_64 3/5
Verifying : Percona-Server-client-55-5.5.35-rel33.0.611.rhel6.x86_64 4/5
Verifying : Percona-Server-devel-55-5.5.35-rel33.0.611.rhel6.x86_64 5/5

Installed:
Percona-Server-client-55.x86_64 0:5.5.35-rel33.0.611.rhel6 Percona-Server-devel-55.x86_64 0:5.5.35-rel33.0.611.rhel6
Percona-Server-server-55.x86_64 0:5.5.35-rel33.0.611.rhel6 Percona-Server-shared-55.x86_64 0:5.5.35-rel33.0.611.rhel6
Percona-Server-shared-compat.x86_64 0:5.5.35-rel33.0.611.rhel6

Complete!

// LOOKS OK more or less - BUT AFTER

Step 5)
[root@falcon238 imdb]# /usr/sbin/mysqld --skip-grant-tables --user=mysql &
[1] 19820
[root@falcon238 imdb]# 140305 10:48:22 [Note] Plugin ‘FEDERATED’ is disabled.
140305 10:48:22 InnoDB: The InnoDB memory heap is disabled
140305 10:48:22 InnoDB: Mutexes and rw_locks use GCC atomic builtins
140305 10:48:22 InnoDB: Compressed tables use zlib 1.2.3
140305 10:48:22 InnoDB: Using Linux native AIO
140305 10:48:22 InnoDB: Initializing buffer pool, size = 128.0M
140305 10:48:22 InnoDB: Completed initialization of buffer pool
InnoDB: Error: log file ./ib_logfile0 is of different size 0 50331648 bytes
InnoDB: than specified in the .cnf file 0 5242880 bytes!
140305 10:48:22 [ERROR] Plugin ‘InnoDB’ init function returned error.
140305 10:48:22 [ERROR] Plugin ‘InnoDB’ registration as a STORAGE ENGINE failed.
140305 10:48:22 [ERROR] Unknown/unsupported storage engine: InnoDB
140305 10:48:22 [ERROR] Aborting

140305 10:48:22 [Note] /usr/sbin/mysqld: Shutdown complete

mysql_upgrade
Looking for ‘mysql’ as: mysql
Looking for ‘mysqlcheck’ as: mysqlcheck
FATAL ERROR: Upgrade failed
#################################################

Have anybody an advice what to try for proper downgrade ?

Best regards
Serge

2

Hi,

It seems, this is the main error.

[COLOR=#252C2F]140305 10:48:22 InnoDB: Completed initialization of buffer pool
[COLOR=#252C2F]InnoDB: Error: log file ./ib_logfile0 is of different size 0 50331648 bytes
[COLOR=#252C2F]InnoDB: than specified in the .cnf file 0 5242880 bytes!

If you have properly shutdown MySQL server before downgrade then all changes should have written into disk. In this case, Can you remove logfiles and try to restart MySQL again? MySQL will create new files when logfiles are not in datadir.

3

Hi and thank you for the hint.
Before
/usr/sbin/mysqld --skip-grant-tables --user=mysql &
I’ve deleted two log files - /var/lib/mysql/ib_logfile0 & /var/lib/mysql/ib_logfile1
and it helped -

but during next stage
mysql_upgrade
I’ve met the following errors

Running ‘mysql_fix_privilege_tables’…
140314 8:02:32 [ERROR] /usr/sbin/mysqld: Incorrect information in file: ‘./mysql/procs_priv.frm’
140314 8:02:32 [ERROR] /usr/sbin/mysqld: Incorrect information in file: ‘./mysql/general_log.frm’
140314 8:02:32 [ERROR] /usr/sbin/mysqld: Incorrect information in file: ‘./mysql/slow_log.frm’
140314 8:02:32 [ERROR] /usr/sbin/mysqld: Incorrect information in file: ‘./performance_schema/events_statements_summary_by_digest.frm’
140314 8:02:32 [ERROR] /usr/sbin/mysqld: Incorrect information in file: ‘./performance_schema/host_cache.frm’
140314 8:02:32 [ERROR] /usr/sbin/mysqld: Incorrect information in file: ‘./performance_schema/events_statements_summary_by_digest.frm’
140314 8:02:32 [ERROR] /usr/sbin/mysqld: Incorrect information in file: ‘./performance_schema/host_cache.frm’
140314 8:02:33 [ERROR] /usr/sbin/mysqld: Incorrect information in file: ‘./mysql/general_log.frm’
140314 8:02:33 [ERROR] /usr/sbin/mysqld: Incorrect information in file: ‘./mysql/slow_log.frm’
140314 8:02:34 [ERROR] /usr/sbin/mysqld: Incorrect information in file: ‘./mysql/procs_priv.frm’
140314 8:02:34 [ERROR] /usr/sbin/mysqld: Incorrect information in file: ‘./mysql/procs_priv.frm’
140314 8:02:34 [ERROR] /usr/sbin/mysqld: Incorrect information in file: ‘./mysql/procs_priv.frm’
140314 8:02:34 [ERROR] /usr/sbin/mysqld: Incorrect information in file: ‘./mysql/procs_priv.frm’
140314 8:02:34 [ERROR] /usr/sbin/mysqld: Incorrect information in file: ‘./mysql/procs_priv.frm’
140314 8:02:36 [ERROR] /usr/sbin/mysqld: Incorrect information in file: ‘./mysql/procs_priv.frm’
ERROR 1033 (HY000) at line 80: Incorrect information in file: ‘./mysql/procs_priv.frm’
ERROR 1033 (HY000) at line 86: Incorrect information in file: ‘./mysql/general_log.frm’
ERROR 1243 (HY000) at line 87: Unknown prepared statement handler (stmt) given to EXECUTE
ERROR 1243 (HY000) at line 88: Unknown prepared statement handler (stmt) given to DEALLOCATE PREPARE
ERROR 1033 (HY000) at line 94: Incorrect information in file: ‘./mysql/slow_log.frm’
ERROR 1243 (HY000) at line 95: Unknown prepared statement handler (stmt) given to EXECUTE
ERROR 1243 (HY000) at line 96: Unknown prepared statement handler (stmt) given to DEALLOCATE PREPARE
ERROR 1033 (HY000) at line 719: Incorrect information in file: ‘./mysql/general_log.frm’
ERROR 1033 (HY000) at line 730: Incorrect information in file: ‘./mysql/slow_log.frm’
ERROR 1033 (HY000) at line 849: Incorrect information in file: ‘./mysql/procs_priv.frm’
ERROR 1033 (HY000) at line 853: Incorrect information in file: ‘./mysql/procs_priv.frm’
ERROR 1033 (HY000) at line 857: Incorrect information in file: ‘./mysql/procs_priv.frm’
ERROR 1033 (HY000) at line 861: Incorrect information in file: ‘./mysql/procs_priv.frm’
ERROR 1033 (HY000) at line 865: Incorrect information in file: ‘./mysql/procs_priv.frm’
ERROR 1033 (HY000) at line 1146: Incorrect information in file: ‘./mysql/procs_priv.frm’
FATAL ERROR: Upgrade failed

So that, please, let me know one more hint how to go through
mysql_upgrade
without the errors.

Waiting for your reply,

4

Hi,

I hope you have checked this before downgrade. [url]https://dev.mysql.com/doc/refman/5.6/en/downgrading-to-previous-series.html[/url]
Generally, for this kind of error for mysql tables solved by creating mysql db from scratch. If you have old backup (of 5.5) then you can also restore those files for specific tables. Something like this [url]innodb - Cannot open table mysql/innodb_index_stats - Database Administrators Stack Exchange and check.