how to recover after power outage

[John Almberg]

>> Check the machine-hostname.err file when you manually try and  
>> start MySQL.
>> Provided that you have mysql_enable="YES" in /etc/rc.conf you  
>> should be able
>> to manually attempt to start with /usr/local/etc/rc.d/mysql-server  
>> start (it
>> seems to work reliably when you type out the entire command path- 
>> wise).
>>
>> Note that if somehow permissions on the my.cnf file got changed  
>> MySQL won't
>> start if my.cnf is world writable. Check for stale PID and  
>> sockets. Normally
>> these shouldn't be a problem as a startup will just overwrite  
>> them. Check
>> these to eliminate any wonkiness, e.g. some permission change  
>> isn't allowing
>> for MySQL to wipe the old ones.
>>
>> The whateverthehostname.err log and possibly /var/log/messages  
>> might give
>> some clue for what's going on. If the database files are corrupt  
>> just clean
>> them out and replace with a backup done with dump. Ensure the /var/ 
>> db/mysql
>> tree is chowned mysql:mysql. If you had to install/reinstall from  
>> ports the
>> install should have created the appropriate uid/gid accounts.  
>> Check and see
>> if these are missing.
>>
>> At any rate I wish you the best of luck. Now that you can SSH in  
>> you can
>> probably fix it up.
>

Okay, so my new database server is running with backup data and I am  
trying to salvage the old database, or what's left of it.

Unfortunately, it seems like what's left of it, is not much.

the /var/db/mysql directory tree is now a file:

qu# ls -l /var/db/mysql
-rwx------  2 mysql  wheel  1024 Jul  5  2008 /var/db/mysql

The situation looks hopeless to me. Is it?

Another question: given that the file system took a major hit, should  
I try to fix it, or just do a clean install? I'm leaning towards the  
clean install since I've been meaning to upgrade this machine to 7.1  
anyway.

Is there anyway to fix the file system, reliably? fsck doesn't seem  
to be able to solve all the problems.

-- John