Mysqld InnoDB crash

Question

my MySQL server just crashed and I cannot restart/recover it. I've tried:

/etc/init.d/mysql restart

Stopping MySQL database server: mysqld.
Starting MySQL database server: mysqld . . . . . . . . . . . . . . failed!

and

mysqld --verbose --innodb_force_recovery=4

120528 18:44:28 [Warning] '--log_slow_queries' is deprecated and will be removed in a future release. Please use ''--slow_query_log'/'--slow_query_log_file'' instead.
120528 18:44:28 [Warning] '--default-character-set' is deprecated and will be removed in a future release. Please use '--character-set-server' instead.
120528 18:44:28 [Note] Plugin 'FEDERATED' is disabled.
InnoDB: The log sequence number in ibdata files does not match
InnoDB: the log sequence number in the ib_logfiles!
120528 18:44:29  InnoDB: Database was not shut down normally!
InnoDB: Starting crash recovery.
InnoDB: Reading tablespace information from the .ibd files...
InnoDB: Restoring possible half-written data pages from the doublewrite
InnoDB: buffer...
Killed

both (as you can see) without success.

I've checked log files at /var/log/mysql, /var/log/mysql.err and /var/log/mysql.log but they are all empty. I don't have any other ideas. Any suggestions?

Answer 1

Check the hardware it's running on; that could be bad ram or a bad CPU (what caused it to crash in the first place?). You might have also hit a mysql bug. You could try updating mysql (minor versions only would be my suggestion), if that's the case.

My first step would be memtest86.

Answer 2

This page addresses your problem exactly.

You may want to look at this MySQL page as well (for 5.0, easily you can switch to 5.1 if necessary).

I would first (server being down) remove the ib_log* files, and try a restart (remove the log files, not the data files). You may have had a log file size change - or a version change - that causes InnoDB to refuse to start.

InnoDB may sometimes be picky about log files.