how to recover after power outage

[John Almberg]

On Apr 5, 2009, at 2:10 PM, Michael Powell wrote:

> John Almberg wrote:
>
> [snip]
>>
>> Okay, so the machine is back online and I can log in again.
>>
>> The hardware is only 18 months old or so... good quality stuff, so
>> hopefully nothing is physically damaged. We'll see...
>>
>> Unfortunately, mysql isn't working at the moment... will make a
>> backup of data (I have the previous night's backup, of course, but
>> would like the latest, if possible.) Then will try to figure out
>> what's working and what's not.
>>
>
> 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.

Well, I had to give up, temporarily, on this server to get my clients  
back online.

I took a nice machine I had laying around, loaded a fresh copy of  
FreeBSD on it, installed mysql, and loaded the Saturday morning  
database backup.

I had to set up all the database permissions correctly, which took  
some time, but I'm happy to say that I've got all my clients back  
online with this new database server.

Now I am going to catch a couple hours sleep (this has been going on  
since 2 am). Once I restore some brain cells, I'll see if I can  
figure out what's happening with the main database server. NYI has  
taken it off line, for some reason, and I can't log into it anyway,  
at the moment.

Thanks for all the helpful advice. It's great to have this list to  
fall back on in a crisis.

Brgds: John