MySQL Connection Error?

[cmdbash]

Yesterday something strange started happening to our Web Server, it started becoming unresponsive and we could not remote into it. Only every few minutes we can make a connection to be booted off again.

 

So we started digging into the log files of the remote servers and found some interesting stuff.

 

07/06/2012 18:46:29 Devart.Data.MySql Can't connect to MySQL server on 'Web Server IP' (10061): Authentication failed.

 

07/06/2012 18:46:44 Devart.Data.MySql Can't connect to MySQL server on 'Web Server IP' (10061):

Server did not respond within the specified timeout interval

 

07/07/2012 00:36:54 Devart.Data.MySql Host 'Remote Server IP' is blocked because of many connection errors; unblock with 'mysqladmin flush-hosts'

 

Now what you see above is a very abridge snippet of what we saw, the first two were repeating every second, and then after 20 minutes of that every single second the third message was coming up, for hours.

 

Now we were able to resolve this issue by simply clearing the hosts and restarting our MySQL service. But whats really strange is we did not change anything and nothing is "new" its as if one of our Remotes decided yesterday was the day to smash the Web Server with MySQL connection attempts.

 

Any ideas on what caused this and how to prevent this?

[LFA]

Try this: http://help.tcadmin.com/Improve_MySQL_Connection_Speed

 

Also check the speed between servers. Another client was having similar errors only on 1 remote. A speed test showed around 0.01KB/s when downloading a file from the master.

[cmdbash]

Try this: http://help.tcadmin.com/Improve_MySQL_Connection_Speed

 

Also check the speed between servers. Another client was having similar errors only on 1 remote. A speed test showed around 0.01KB/s when downloading a file from the master.

 

Thanks LFA, I have added that to our MySQL. Hopefully we wont see it again.

 

Speed test showed all clear.

[cmdbash]

Just coming back around to this, the issue is now effecting all of our servers, when this happens it severally impacts the performance of the entire server thus our customers are not happy.

 

Any further thoughts? Its not constant, it happens for 5-10 minutes at a time, once a day.

[LFA]

It is probably network errors between the servers.