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From:Claudio Nanni Date:June 12 2012 8:26pm
Subject:Re: Aborted clients
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Howard,

a client can be blacklisted, but in that case is   Aborted connection  to
be increased since the connection request is refused upfront.

@Johan, you say "I'm having trouble with clients aborting, but for some
reason they don't get logged."

could you please tell which exactly is the problem?

1) Aborted clients counter gets increased
2) Increasing Aborted clients has a measurable impact on the application
3) ...

Thanks

Claudio

2012/6/12 Howard Hart <hch@stripped>

> On 06/12/2012 05:10 AM, Johan De Meersman wrote:
>
>  ----- Original Message -----
>>
>>  From: "Claudio Nanni"<claudio.nanni@stripped**>
>>> " Print out warnings such as Aborted connection... to the error log."
>>> the dots are not telling if they comprise Aborted clients as well.
>>>
>> Hah, how's that for selective blindness. Totally missed that :-)
>>
>>  I find the MySQL error log extremely poor, as far as I know it is one
>>> of the MySQL features (like authentication) stuck to the dawn of
>>> MySQL times.
>>> Very hard to debug non basic things like your issue.
>>>  From what I have experienced usually Aborted connection means wrong
>>> credentials while Aborted clients means the client (typically PHP)
>>> did not close the connection properly.
>>>
>> Yep, that's it; but indeed, since aborted clients aren't logged, then, I
>> seem to be in a ditch.
>>
>>  Do you have any chance to check if the code is closing the
>>> connections to the mysql database?
>>>
>> Oh, yes, millions upon billions of lines of wonderfully obscure Java
>> stacktraces that reveal little more than "Lost connection to database" for
>> every couple of thousand lines.
>>
>> Everything works fine most of the time, then randomly some queries will
>> get slow, and eventually the connections will drop. Rinse and repeat.
>>
>> Oh well. Thanks for pointing out my reading error, I'm off to lart the
>> devs into profiling their code to figure out *what* causes the slowness.
>> Guess I'll have to set up some tcpdumps, too.
>>
>>  Watch out for this one, especially if the Aborted connections are all
> getting charged against a single client. Per the URL below and a
> misbehaving application not closing connections correctly, I've seen this
> spontaneously blacklist a client IP. Only way to unblacklist after is to
> run "flush-hosts" on the mysql server.
>
> Also, didn't see a one-to-one correspondence between the global
>  max_connect_errors setting and Aborted_connects (from show global status
> like '%abort%';), so hard to tell when you're approaching the per client
> blacklist limit.
>
>
> http://dev.mysql.com/doc/**refman/5.0/en/blocked-host.**html<http://dev.mysql.com/doc/refman/5.0/en/blocked-host.html>
>
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>


-- 
Claudio

Thread
Aborted clientsJohan De Meersman12 Jun
  • Re: Aborted clientsClaudio Nanni12 Jun
    • Re: Aborted clientsAnanda Kumar12 Jun
      • Re: Aborted clientsAnanda Kumar12 Jun
        • Re: Aborted clientsJohan De Meersman12 Jun
    • Re: Aborted clientsJohan De Meersman12 Jun
      • Re: Aborted clientsHoward Hart12 Jun
        • Re: Aborted clientsClaudio Nanni12 Jun
          • Re: Aborted clientsJohan De Meersman13 Jun
            • Re: Aborted clientsClaudio Nanni13 Jun
              • Re: Aborted clientsAnanda Kumar13 Jun
              • Re: Aborted clientsJohan De Meersman13 Jun