A bit about bits.

Use these instructions to retrieve local address information.

[hostname]
println InetAddress.localHost.canonicalHostName

[ip address]
println InetAddress.localHost.hostAddress

Hi,

After several hours at google, I finally got a reasonable and functional solution for the MySQL broken pipe issue.

You see, my first attempted solution was to update the configuration in the [DataSource.groovy] file and to insert a Spring bean in [resource.groovy]. Something like this:

production {
		dataSource {
			dbCreate = "update"
			url = "jdbc:mysql://localhost:3306/st?autoReconnect=true"
			driverClassName = "com.mysql.jdbc.Driver"
			username = "st_user"
			password = "st_pass1"

                        minEvictableIdleTimeMillis=1800000
                        timeBetweenEvictionRunsMillis=1800000
                        numTestsPerEvictionRun=3

                        validationQuery="SELECT 1 from dual"
                        testOnBorrow=true
                        testOnReturn=true
                        testWhileIdle=true
		}
	}

and

import grails.util.GrailsUtil
import com.mchange.v2.c3p0.ComboPooledDataSource
import org.codehaus.groovy.grails.commons.GrailsApplication
import org.codehaus.groovy.grails.commons.ConfigurationHolder as CH 

beans = { 

   if (GrailsUtil.environment != GrailsApplication.ENV_TEST) {
      dataSource(ComboPooledDataSource) { bean ->
         bean.destroyMethod = 'close'
         user = CH.config.dataSource.username
         password = CH.config.dataSource.password
         driverClass = CH.config.dataSource.driverClassName
         jdbcUrl = CH.config.dataSource.url
         initialPoolSize = 10
         minPoolSize = 10
         maxPoolSize = 50
         maxStatements = 240
         maxConnectionAge = 60 * 60 * 2 // 2 hours
         maxIdleTime = 60 * 60 // 1 hour
         idleConnectionTestPeriod = 240
         testConnectionOnCheckin = true
         testConnectionOnCheckout = true
         automaticTestTable = "c3p0_test"
      }
   }
}

Nevertheless the problem still persisted, besides the frustration I haven’t lost my faith and restarted the research again.

So, I finally got this article at: http://sacharya.com/grails-dbcp-stale-connections/

The solution is very simple, one just creates a groovy class in grails ([src/groovy] folder) within this code:

package ...your package...

import org.apache.log4j.Logger
import org.codehaus.groovy.grails.commons.ApplicationAttributes

class DataSourceUtils {

    static final Logger log = Logger.getLogger(DataSourceUtils)

    //
    // fix for the database killing idle connections
    //
    // http://sacharya.com/grails-dbcp-stale-connections/
    //
    private static final ms = 1000 * 15 * 60

    public static tune = { servletContext ->

        def ctx = servletContext.getAttribute(ApplicationAttributes.APPLICATION_CONTEXT)
        ctx.dataSource.with {d ->
            d.setMinEvictableIdleTimeMillis(ms)
            d.setTimeBetweenEvictionRunsMillis(ms)
            d.setNumTestsPerEvictionRun(3)
            d.setTestOnBorrow(true)
            d.setTestWhileIdle(true)
            d.setTestOnReturn(true)
            d.setValidationQuery('select 1')
            d.setMinIdle(1)
            d.setMaxActive(16)
            d.setInitialSize(8)
        }

        if (log.infoEnabled) {
            log.info "Configured Datasource properties:"
            ctx.dataSource.properties.findAll {k, v -> !k.contains('password') }.each {p ->
                log.info "  $p"
            }
        }
    }
}

and then, update the [BootStrap.groovy] file in order to invoke the inserted class:

import ...your package... .DataSourceUtils

class BootStrap {

     def init = { servletContext ->
        DataSourceUtils.tune(servletContext)
     }
}

and voilà… there you go!

For more information about this issue and it’s solution, see the Sudarshan Acharya blog site (http://sacharya.com/grails-dbcp-stale-connections/) it is very good and well explained.