Another InnoDB crash

It happened twice in May, and now again: another InnoDB crash. db4free.net is now up again with a fresh server instance, meaning that no databases have been transferred from the old server to the new one.

However, the old server is still accessible. It’s running in recovery mode which is good enough to allow you to create a backup of your data (and transfer it to a new account on the new MySQL server instance, if you wish). Here is how to do it.

Make sure you have mysql and mysqldump available on your system. Linux users can usually install the mysql-client package by the distribution’s package manager. OS X users can get it at http://dev.mysql.com/downloads/mysql/5.6.html. For Windows users I am providing mysql.exe and mysqldump.exe for your convenience. Put them somewhere where you can access them by the command prompt.

Here are the commands to first create a dump file (from the old server), and then to import it in the new server instance:

mysqldump -h db4free.net -P 3307 -u [username] -p[password] --databases [database_name] --opt > dump.sql
mysql -h db4free.net -u [username] -p[password] [database_name] < dump.sql

Of course you need to use the correct username/password/database name; with mysqldump those from the old server (now running on port 3307), and with the mysql command from the new server.

Please understand that I can’t give individual support. But this should get you started and there is a lot of information out there in the World Wide Web.

So why didn’t I transfer the data? Well, I tried. But the amount of data was so huge that I ran into all kinds of limits and timeouts that I gave up. One reason was that there are some individual users who host a huge amount of data on db4free.net, in fact only a few users accounted for the majority of data. Which is why I am introducing a new rule on the new server: only a maximum of 100 MB is allowed per database, and databases which exceed 100 MB will be cleared at irregular intervals, with no warning! Remember: db4free.net is a testing service, no hosting service. If you need safety you should get an account with a commercial provider that can give you the kinds of guarantees which db4free.net can’t give you.

I am also asking you to delete data which you no longer need, or even delete the account. When another crash occurs (which is not so unlikely, as it happened 3 times in slightly more than 6 months) chances that I can migrate the data to a new server instance are much better if the data load is smaller. So please help and don’t leave unnecessary data laying around.

Please don’t waste time to get a dump of your data (if you need it). My plan is to leave the old server instance running until end of October. But as always, data corruption can happen, even on this server instance. So make sure you get what you need (even though you shouldn’t … remember why?).

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