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I am trying to use roundcube and it recently just broke. I don't know if this is due to a MySQL update that happened recently or not but in phpMyAdmin I get the following error if I try and view a table:

1286 - Unknown storage engine 'InnoDB'


| Engine             | Support | Comment                                                        | Transactions | XA   | Savepoints |
| MRG_MYISAM         | YES     | Collection of identical MyISAM tables                          | NO           | NO   | NO         |
| CSV                | YES     | CSV storage engine                                             | NO           | NO   | NO         |
| MyISAM             | DEFAULT | MyISAM storage engine                                          | NO           | NO   | NO         |
| BLACKHOLE          | YES     | /dev/null storage engine (anything you write to it disappears) | NO           | NO   | NO         |
| FEDERATED          | NO      | Federated MySQL storage engine                                 | NULL         | NULL | NULL       |
| PERFORMANCE_SCHEMA | YES     | Performance Schema                                             | NO           | NO   | NO         |
| ARCHIVE            | YES     | Archive storage engine                                         | NO           | NO   | NO         |
| MEMORY             | YES     | Hash based, stored in memory, useful for temporary tables      | NO           | NO   | NO         |
8 rows in set (0.00 sec)


max_connections = 500
max_user_connections = 20
key_buffer = 512M
myisam_sort_buffer_size = 64M
join_buffer_size = 64M
read_buffer_size = 12M
sort_buffer_size = 12M
read_rnd_buffer_size = 12M
table_cache = 2048
thread_cache_size = 16K
wait_timeout = 30
connect_timeout = 15
tmp_table_size = 64M
max_heap_table_size = 64M
max_allowed_packet = 64M
max_connect_errors = 10
query_cache_limit = 1M
query_cache_size = 64M
query_cache_type = 1
open_files_limit = 8192

max_allowed_packet = 512M

key_buffer = 64M
sort_buffer = 64M
read_buffer = 16M
write_buffer = 16M

Ideas as to how to fix? It used to work just fine.

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Check what mysql error log (/var/log/mysql/error.log) says on startup. – Kazimieras Aliulis Jun 5 '13 at 13:12


  • I see there is nothing Innodb-related in the my.cnf.
  • Look for Innodb-related error messages expressing why mysqld failed to start in the error log.

My first guess would be look at the ib_logfile0 and ib_logfile1 in /var/lib/mysql.

If they have been set to size different from the default, that probably will prevent mysqld's startup. The default for innodb_log_file_size is 5M.


If RoundCube's installation overwrote the my.cnf, see if you have a physical backup of the previous my.cnf. Put that back in place and run

service mysql start


Take the filesize of ib_logfile0 and divide by 1048576. Let's say it is 12M.

Put that in my.cnf

innodb_log_file_size = 12M

then run

service mysql start

Give it a Try !!!

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You may want to check this link:

Some of the things that are mentioned in the article: 1. Deleting innodb log files. 2. Changing innodb_buffer_pool_size to lower then 2G

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When you have disable innodb, dont' forget to remove all innodb-related tables from Dbs. For example "mysql" database has 5 of them:$ mysql mysql -e 'show table status' | grep Unknown | awk '{print $1}'
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Just delete ib_logfileX files and restart mysql service.

You changed the innodb-log-file-size var to size more bigger than already set it in your mysql daemon.

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I've edited your post. Please use punctuation and full words next time. "u" is not a word ;) – ypercubeᵀᴹ Aug 2 '15 at 23:41

I use roundcube, apache2, mysql, dovecot, postfix. After harddisk crash and reinstall the same system on a new one HDD I cannot connect to the mail server by web application (roundcube). Teh message was "Unknown storage engine 'InnoDB'". About 2 weeks of searching the fault configuration without results and by a miracle, today, I saw that someone of the linux components cannot write in /tmp. That's all what I did ... put chmod 1777 /tmp ... Now it's running ok! Good luck!

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