It seems that startup is failing due to corruption in a database that we have already dropped.
MySQL is not starting, and the log shows the following error (a few hundred):
170905 5:46:05 InnoDB: Error: page 1 log sequence number 87166865838
and the DB could be corrupt and to see: http://dev.mysql.com/doc/refman/5.5/en/forcing-innodb-recovery.html
As suggested, we started MySQL with innodb_force_recovery = 2 and innodb_purge_threads = 0, backed up the databases, and then dropped the database with the corrupted table(s).
MySQL still does not start. The error log ASCII/HEX dump shows segments of data that was in the deleted database.
Why are we still having problems with the deleted database? It feels like a process is still hanging, or something might not have deleted properly.
Any ideas? Thanks
Using MySQL 5.5.3 on Ubuntu 14.04
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I have a C# application performing some database operations on a MySQL 5.7 server. Once the complete system hunp up and I had to hard-reset it. When it comes to a specific table read/write operation now the database server crashes. The windows log shows
InnoDB: Trying to access page number 286720 in space 29,
space name myInstance/myTable, which is outside the tablespace bounds.
Byte offset 0, len 16384, i/o type read.
I tried to use mysqlcheck --repair but it fails because note : The storage engine for the table doesn't support repair.
I've read some advices that say I should start MySQL in a recovery mode, so I added
[mysqld]
innodb_force_recovery=4
to the my.ini config file whereupon I should be able to use mysqldump to export the affected database table. But unfortunatelly I am not.
mysqldump: Error 2013: Lost connection to MySQL server
during query when dumping table `myTable` at row: 1246
Edit:
I checked the error log again and found lots of entries saying
[ERROR] C:\Program Files\MySQL\MySQL Server 5.7\bin\mysqld.exe:
The table 'myTable' is full
I'm running the server on a Windows 32bit OS with an NTFS formatted partition. The myTable.ibd file size is around 4.5 GB, checking C.10.3 Limits on Table Size states a file size limit of "2TB (possibly larger)" for Win32 w/ NTFS.
While checking the reasons for my error the only possible cause I found was a full InnoDB tablespace. The solution might be "Changing the Number or Size of InnoDB Redo Log Files" although the coherence is a bit vague to me. Nevertheless I increased the size of the Redo Log Files from 48M to 100M. But nothing changed.
If I perform a SQL select * from myTable order by Id desc the server crashes instantly. Error log entry is exactly the same as above.
I checked the chapter 15.7.1 Resizing the InnoDB System Tablespace as well and found out that innodb_data_file_path is not explicitly specified.
Any ideas what I can do now? Thanks a lot!
InnoDB cannot repair corruption in tablespaces. This was never implemented and mysqlcheck won't help in any way.
The corruption is in space id 29 which is table myInstance.myTable. To repair it you need to dump all records from this table with innodb_force_recovery. Try all values from 4 to 6 until MySQL doesn't crash. Then drop the table and reload the dump.
If MySQL crashes even with innodb_force_recovery=6 then restore the table from backup.
If you don't have backup - use script http://bazaar.launchpad.net/~percona-dev/percona-data-recovery-tool-for-innodb/trunk/view/head:/fetch_data.sh . It will fetch as many records as it can.
One possible cause could be that the ib_logfile* files are corrupted.
To fix this, remove these files using rm ib_logfile*.
Where are these files?
These files are in mysql datadir. The location of datadir depends on the OS. Check my.cnf, in osx that should be in /usr/local/etc.
I have a Master - Slave setup with MySql v5.1.39 running ~10 db's on 12 core Linux machine. I had to move the bin-log files to a separate disk for performance issues. So I followed these steps:
Stop everything that's using the db
Stop Slave
Stop master
Change paths in /my.cfg to /mysql/log/* to /mysql/newlog/* on master and slave
Copy /mysql/log/* to /mysql/newlog/. on master and slave
Start Slave
All Ok!
Start Master
First problem! on the slave:
150113 12:21:22 [ERROR] Got fatal error 1236: 'Could not find first log file name in binary log index file' from master when reading data from binary log
150113 12:21:22 [Note] Slave I/O thread exiting, read up to log 'bin-log.005523', position 716864371
Now a quick Google didn't resolve anything and since downtime is an issue. I stopped the Master, changed the configuration back and restarted. Now the second "problem"!
...
150113 13:02:22 InnoDB: Error: page 182380 log sequence number 3407 300161079
InnoDB: is in the future! Current system log sequence number 3407 299353326.
InnoDB: Your database may be corrupt or you may have copied the InnoDB
InnoDB: tablespace but not the InnoDB log files. See
InnoDB: http://dev.mysql.com/doc/refman/5.1/en/forcing-recovery.html
InnoDB: for more information.
...
I quote problem because everything works fine. Replication to the slave restarted and worked. I started the applications and those work fine. But when start MySql on the Master, I get the errors above, about 50 of them with different page- and sequence numbers.
How does moving files affect page- and sequence numbers and where do they come from? How big is my problem? everything seems to work fine.
Please ask if you need anymore information and thanks for your help.
First problem was caused by the file /mysql/log/bin-log.index. I forgot to change the contents of this file to point to the new directory of the log files:
/mysql/log/bin-log.000028 -> /mysql/newlog/bin-log.000028
/mysql/log/bin-log.000029 -> /mysql/newlog/bin-log.000029
/mysql/log/bin-log.000030 -> /mysql/newlog/bin-log.000030
/mysql/log/bin-log.000031 -> /mysql/newlog/bin-log.000031
The second problem was caused by the timestamps of some files. I should have preserved the timestamps with cp -p log/* newlog/. or rsync -avrx log/* newlog/..
I recently experienced a DDoS attack. It overwhelmed and crashed my server. Upon restart all of the innodb tables were corrupted in every database on the server.
I have since rebuilt the databases and all of the tables. I had to recreate innodb_table_stats, innodb_index_stats.
Everything now seems to be running fine, the website is up but I have one persistent error that keeps coming up. The general log is filling with these quite rapidly.
2014-07-13 15:28:37 7fd70b374700 InnoDB: Error: page 193 log sequence number 526819726
InnoDB: is in the future! Current system log sequence number 156433332.
InnoDB: Your database may be corrupt or you may have copied the InnoDB
InnoDB: tablespace but not the InnoDB log files. See
InnoDB: http://dev.mysql.com/doc/refman/5.6/en/forcing-innodb-recovery.html
InnoDB: for more information.
I tried Changing the Number and Size of mySQL logs. It all went fine with no errors. But I am still seeing these errors mount up in the new log.
What else can I try to sync up these log sequence numbers? I am pretty new to this backend database work. Being forced to learn since my hosts tech support sucks.
I am currently on: CENTOS 6.5 x86_64 virtuozzo – vps- WHM 11.44.0 (build 22)
mySQL: 5.6.17
"page ... log sequence number" is when the page was last modified. The LSN in the header is larger than one in the redo log.
The easiest way to fix it is to rebuild the table with noop ALTER TABLE.
ALTER TABLE mytable ENGINE InnoDB;
It will rebuild PRIMARY index as well as its secondary indexes. After that the error should go away.
The ALTER is going to block the table, so if it's large and if the site is in production the best option is to rebuild it with pt-online-schema-change. It will do the same, but won't block the table but for brief moment.
pt-online-schema-change --alter "ENGINE=InnoDB" D=sakila,t=actor
I had a running MySQL server on my mac with XAMPP, however my computer unexpectedly shut down, and when I restarted it and accessed my DB, it gave me the error:
db.table does not exist
When I investigated further, I realized that the .ibd file still exist, and therefore I extracted them. Then, I tried to remove the database to re-add the .ibd files. However, it fails. How can I restore my tables?
Do you have still the create statements for your table or can you recreate them?
Then you can Recover an InnoDB table from only an .ibd file
I fairly new to MySQL database. I am repeatedly seeing an error from MySQL saying the table is marked as crashed and should be repaired. However I am able to repair the crashed table by using the command myisamchk. By the way, I am using MYISAM database engine in MySQL.
I just wanted to know under what circumstances would a DB table crash and how I can prevent it from happening again?
I am connecting to MySQL(5.0) database from Tcl (8.5) script using mysqltcl library (3.0).
MyISAM tables are very easy to crash. There is header info in each table that keeps track of how many open file handles a MyISAM table has.
If mysqld crashes, any MyISAM table that had open file handles to it never had the opportunity to decrement the file handle count upon each file handle closing. Thus, if a new file handle opens a MyISAM table (.MYD file) and mysqld discovers a mismatch between the number of file handles a MyISAM table believes is open and the the number of file handles the MyISAM table actually has open, the table is declared crashed.
There are four(4) methods for handling this:
METHOD #1 : Setup automatic MyISAM repair
See my post https://dba.stackexchange.com/a/15079/877 on how to set this up upon a MySQL restart (Mar 15, 2012)
METHOD #2 : Use InnoDB instead of MyISAM
InnoDB has crash recovery built into the Storage Engine's initialization. MyISAM does not
METHOD #3 : Use Aria instead of MyISAM
Aria is MariaDB's drop-in replacement for MyISAM. It features crash recovery mechanisms for individual tables.
METHOD #4 : Don't kill -9 on mysqld
If mysqld crashes, deliberately or involuntarily, header info for all open MyISAM tables will get them into a crashed state. Avoid having to manually kill mysqld.
I noticed that when I attempt to do a LVM snapshot of my database volume, after running FLUSH TABLES WITH READ LOCK, then rsync that snapshot to a new system, the tables are marked as crashed and have to be repaired.
I suspect this has to do with there being a file handle on the original machine with the table open, and then I'm syncing the that status to the new machine and it sees a mismatch in the file handles and decides it needs to repair.
This repair is problematic because it takes hours (it is a giant table). So the only reliable way to actually get a snapshot that isn't crashed is to shutdown the database before taking the snapshot, but then I cannot get the SHOW MASTER STATUS to setup replication.