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SQLException: I/O Error: Read timed out

I have a Java Spring application connecting to a SQL Server database.
The connection settings are:
<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"
destroy-method="close">
<property name="driverClass" value="net.sourceforge.jtds.jdbc.Driver" />
<property name="jdbcUrl"
value="jdbc:jtds:sqlserver://${db.host}:1433/TestDB" />
<property name="user" value="${db.user}" />
<property name="password" value="${db.pass}" />
<!-- these are connection pool properties for C3P0 -->
<property name="minPoolSize" value="10" />
<property name="maxPoolSize" value="100" />
<property name="acquireIncrement" value="5"/>
<property name="maxIdleTime" value="30000" />
</bean>
everything works fine but sometimes I got the following error:
Could not open JDBC Connection for the transaction; nested exception is java.sql.SQLException: I/O Error: Read timed out
I have searched a lot but can't find any clue, any idea or help?
I'm using
<bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate">
<constructor-arg index="0" ref="sqlSessionFactory" />
</bean>
in my spring-config xml to get my sqlSession, and in the DAO I use:
#Autowired
SqlSession sqlSession;
and then I execute the queries I want. Is it possible that because the connection is not closed that this error exists?

In my case connections were getting dropped when the nightly db backup job triggered. I'm using jtds/sql-server as well. Here is what I did to fix it:
Create/setup a health-check cron job that executes a simple query from within your application, like a short select from. Call it every 10 minutes or so and log the result. It will give you some feedback about when and why this is happening.
Reduce the idle time parameter (maxIdleTime) in your configuration so that old connections get automatically discarded.
Keep in mind that if you don't change the maxIdleTime and you keep multiple connections open, some of them may remain in a bad state even if you are using the health-check function. Quoting from c3p0 documentation:
By default, pools will never expire Connections. If you wish Connections to be expired over time in order to maintain "freshness", set maxIdleTime and/or maxConnectionAge. maxIdleTime defines how many seconds a Connection should be permitted to go unused before being culled from the pool. maxConnectionAge forces the pool to cull any Connections that were acquired from the database more than the set number of seconds in the past.
Another way to setup a health-check call is by using the idleConnectionTestPeriod parameter. Also check this answer which can give you more ideas on how to set it up.

Existing code throws this error [Hibernate + c3p0 + Oracle11g]: a resourcepool could not acquire a resource from its primary factory or source

when i am trying to connect to a test db which settings as per shown, i am faced all the errors as per mentioned.
most of the config is taken from working production environment but i am not able to connect to my test db.
i have tried various methods and it just fails to run properly.
Im able to connect test db via other methods such as PLSQL developer or SQLPLUS.
The errors i am getting in a bunch are :
org.hibernate.exception.GenericJDBCException: Cannot open connection
....
....
....
Caused by: java.sql.SQLException: Connections could not be acquired from the underlying database!
....
....
....
Caused by: com.mchange.v2.resourcepool.CannotAcquireResourceException: A ResourcePool could not acquire a resource from its primary factory or source.
at com.mchange.v2.resourcepool.BasicResourcePool.awaitAvailable(BasicResourcePool.j‌​ava:1422)
at com.mchange.v2.resourcepool.BasicResourcePool.prelimCheckoutResource(BasicResour‌​cePool.java:606)
at com.mchange.v2.resourcepool.BasicResourcePool.checkoutResource(BasicResourcePool‌​.java:526)
at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool.checkoutAndMarkConnectionInUse‌​(C3P0PooledConnectionPool.java:756) at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool.checkoutPooledConnection(C3P0P‌​ooledConnectionPool.java:683)
this is my config file for hibernate :
<session-factory>
<property name="hibernate.connection.url">jdbc:oracle:thin:#ipaddress:1521:dbname</property>
<property name="hibernate.connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
<property name="hibernate.connection.username">user</property>
<property name="hibernate.connection.password">password</property>
<property name="connection.autoReconnect">true</property>
<property name="connection.autoReconnectForPools">true</property>
<property name="connection.is-connection-validation-required">true</property>
<property name="hibernate.connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</property>
<property name="hibernate.c3p0.max_size">1</property>
<property name="hibernate.c3p0.min_size">1</property>
<property name="hibernate.c3p0.timeout">50000</property>
<property name="hibernate.c3p0.max_statements">100</property>
<property name="hibernate.c3p0.idle_test_period">3000</property>
<property name="hibernate.c3p0.acquire_increment">1</property>
<property name="hibernate.c3p0.validate">false</property>
<property name="dialect">org.hibernate.dialect.Oracle10gDialect</property>
<property name="hibernate.show_sql">true</property>
<property name="hibernate.transaction.factory_class">org.hibernate.transaction.JDBCTransactionFactory</property>
<mapping resource etc>
</session-factory>
Can anyone help me on this issue?

It happen for many reason like
The database configuration details you have entered are incorrect or have changed, e.g. the database name or database username/password for your Confluence database.
1)The URL for the database is incorrect.
2)The database server is not running. If your database server is down, restart it and check the logs to see why it had failed or stopped.
3)The network is down (or there is a firewall in between confluence and the database server which is interfering) and the connection to the database cannot be established.
4)Your database password has expired.
5)Check your driver,if its present or not in your class-path.

Spring datasource :- Your network access was interrupted

I have created a Spring web application for reading ms access large database file. Sometime this file is repaired due to large size. Before compacting database file all open sessions are closed. After closing session and repairing database when we connect to database from spring web application then i get the following error.
HTTP Status 500 - Request processing failed; nested exception is
org.springframework.dao.TransientDataAccessResourceException: PreparedStatementCallback;
SQL [select [DateTimeEntered],[GoodWeight],[MachineSpeed],[GradeCode],[RejectedWeight]
from [tblMachineProduction] where [DateTimeEntered] between ? and ? order by
[DateTimeEntered]]; [Microsoft][ODBC Microsoft Access Driver] Your network access was
interrupted. To continue, close the database, and then open it again.; nested exception
is java.sql.SQLException: [Microsoft][ODBC Microsoft Access Driver] Your network access
was interrupted. To continue, close the database, and then open it again.
How to hanlde this exception or how to reload/ initialize data source.
Spring code is here:-
<bean id="dataSource" scope="prototype" class="org.apache.commons.dbcp.BasicDataSource"
destroy-method="close">
<property name="driverClassName" value="${jdbc.driverClassName}" />
<property name="url" value="${jdbc.database.url}" />
<property name="username" value="${jdbc.username}" />
<property name="password" value="${jdbc.password}" />
<property name="testOnBorrow" value="true"/>
<property name="testOnReturn" value="true"/>
<property name="testWhileIdle" value="true"/>
</bean>

Re-establishing a db connection after a network failure - Hibernate

Hello everyone,
I am using hibernate ORM and oracle database. My cfg file has following properties:
<property name="connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
<property name="connection.url">jdbc:oracle:thin:#url</property>
<property name="connection.username">username</property>
<property name="connection.password">pasword</property>
<property name="dialect">org.hibernate.dialect.Oracle9Dialect</property>
<property name="hibernate.c3p0.min_size">5</property>
<property name="hibernate.c3p0.max_size">20</property>
<property name="hibernate.c3p0.timeout">300</property>
<property name="hibernate.c3p0.max_statements">50</property>
<property name="hibernate.c3p0.idle_test_period">3000</property>
<property name="hibernate.c3p0.acquire_increment">3</property>
Everything works fine, but when I run the application and if I unplug network cable and plug it agian my db queries fail. It gives me the error
java.sql.SQLException: Io exception: Connection reset by peer: socket write error
Is there any way to re establish the connection?

You need to configure your database connection pool - not hibernate.Try setting idleConnectionTestPeriod and an appropriate preferredTestQuery, e.g., select 1 from dual.
See How To Configure The C3P0 ConnectionPool for more information. You'll get the most control if you create a c3p0.properties file in WEB-INF/classes but you need to make sure not to override those properties in your hibernate.cfg.xml.
Well I had written c3p0-config.xml like
<c3p0-config>
<default-config>
<!-- Configuring Connection Testing -->
<!-- property name="automaticTestTable">TEST_EMS_HIBERNATE_CONN</property -->
<property name="checkoutTimeout">0</property>
<property name="testConnectionOnCheckout">true</property>
<property name="testConnectionOnCheckin">false</property>
<property name="preferredTestQuery">SELECT 1 from dual</property>
<!-- Configuring Recovery From Database Outages -->
<property name="acquireRetryAttempts">0</property>
<property name="acquireRetryDelay">1000</property>
<property name="breakAfterAcquireFailure">false</property>
<!-- Configuring to Debug and Workaround Broken Client Apps -->
<property name="unreturnedConnectionTimeout">1800</property>
<property name="debugUnreturnedConnectionStackTraces">true</property>
</default-config>
and the system properties like:
C3P0_SYS_PROPS="-Dcom.mchange.v2.c3p0.cfg.xml=<FILE-PATH>/c3p0-config.xml -Dcom.mchange.v2.log.MLog=com.mchange.v2.log.FallbackMLog -Dcom.mchange.v2.log.FallbackMLog.DE
FAULT_CUTOFF_LEVEL=WARNING"

As I see, you have specified when test connection, but have not specified how to test them. Read it http://www.mchange.com/projects/c3p0/index.html#configuring_connection_testing . I guess you should just add preferredTestQuery, usually it's something like SELECT 1 FROM DUAL.
Also read here Something wrong with Hibernate DB connection pooler c3p0

Can't open connection

I develop an applivation with very load(request).
I used following technologies in my appliation:
Jpa/Hibernate as persistense layer
Spring and Spring Dao
C3p0 as connection pooling
my problem is : I run my application , when number of request increase, throw exception in
persistense layer that"Cannt open connection"
I increase oracle max session but my problem not solve
I indept in C3p0 document and test its options but my problem not solve.
Thank you for your attention

You increased max sessions on Oracle, but you didn't increase the max size of your connection pool. The exception is telling you that your pool is exhausted. Either find what's holding connections open and get them released sooner, or increase the number of max active connections in the pool.

Is it possible for you to post the Spring configuration for your DataSource. I would expect something like:
<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close">
<property name="driverClass" value="oracle.jdbc.driver.OracleDriver"/>
<property name="jdbcUrl" value="${jdbc.connection.url}"/>
<property name="user" value="${jdbc.connection.username}"/>
<property name="password" value="${jdbc.connection.password}"/>
<property name="initialPoolSize" value="5"/>
<property name="minPoolSize" value="5"/>
<property name="maxPoolSize" value="100"/>
</bean>
With another bean configured where the dataSource is passed by reference:
<bean id="mySampleDao" class="com.example.dao.MySampleDao">
<property name="dataSource" ref="dataSource" />
</bean>
Is this what you have?
What version of Oracle are you using?