Sign up ×
Database Administrators Stack Exchange is a question and answer site for database professionals who wish to improve their database skills and learn from others in the community. It's 100% free, no registration required.

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.

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

5 Answers 5


  • 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 !!!

share|improve this answer

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

share|improve this answer

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}'
share|improve this answer

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.

share|improve this answer
I've edited your post. Please use punctuation and full words next time. "u" is not a word ;) – ypercube Aug 2 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!

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.