Once I deploy my Java Application to IBM Bluemix, it can't create the initial database connection due to this error:
Building new Hibernate SessionFactory 2015-04-11 14:24:04 [main] ERROR
o.h.util.JDBCExceptionReporter - Cannot create
PoolableConnectionFactory (Communications link failure The last packet
sent successfully to the server was 0 milliseconds ago. The driver has
not received any packets from the server.)
I tried to set the "hibernate.current_session_context_class" to "thread" (which solved the problem when I deployed the same app to Google Application Engine) but that didn't help with Websphere Liberty Profile:
<prop key="hibernate.current_session_context_class" >
thread
</prop>
Any ideas?
UPDATE 1 --- This is the actual root cause. Bluemix offers the ClearDB MySQL service but its pipeline cannot connect to it :(
Building new Hibernate SessionFactory 2015-04-11 15:04:49 [main] ERROR
o.h.util.JDBCExceptionReporter - Communications link failure
The last packet sent successfully to the server was 0 milliseconds
ago. The driver has not received any packets from the server.
UPDATE 2 --- Even the Experimental MySQL DB is also off limits if there's any attempt to connect from the pipeline machines:
o.h.util.JDBCExceptionReporter - Cannot create
PoolableConnectionFactory (Communications link failure
The last packet sent successfully to the server was 0 milliseconds
ago. The driver has not received any packets from the server.)
org.hibernate.exception.GenericJDBCException: Cannot open connection
at
org.hibernate.exception.SQLStateConverter.handledNonSpecificException(SQLStateConverter.java:140)
at org.hibe at
org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:115)
at
org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:75)
Caused by: org.apache.commons.dbcp.SQLNestedException: Cannot create
PoolableConnectionFactory (Communications link failure
The last packet sent successfully to the server was 0 milliseconds
ago. The driver has not received any packets from the server.) at
org.apache.commons.dbcp.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:1549)
at
org.apache.commons.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1388)
at
org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:1044)
at
org.springframework.orm.hibernate3.LocalDataSourceConnectionProvider.getConnection(LocalDataSourceConnectionProvider.java:81)
at
org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:446)
... 40 more Caused by:
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException:
Communications link failure
Please let me know if you have any ideas.
Ah ok. So this is happening because the Liberty buildpack autowires in JDBC connections for you during deployment to Bluemix. For the unit tests you will need to provide this connection info to your app.
Related
Could you please guide me How can I connect my local SQL developer to MY SQL Server running on Docker container in EC2. But I havent installed mysql in my ec2 host.
I have tried with public dns and port 3306 but getting below error
An error occurred while establishing the connection:
`Long Message:
Communications link failure
The last packet successfully received from the server was 353 milliseconds ago. The last packet sent successfully to the server was 339 milliseconds ago.
Details:
Type: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException
SQL State: 08S01`
follow the guide in this official AWS documentation
https://aws.amazon.com/premiumsupport/knowledge-center/connect-http-https-ec2/
Use port 3306 however, this is a guide for webservers
When I run maven test locally is passed. But got this error when I run it on CI server.
Error Message
Could not open JPA EntityManager for transaction; nested exception is org.hibernate.exception.JDBCConnectionException: Unable to acquire JDBC Connection
Stacktrace
org.springframework.transaction.CannotCreateTransactionException: Could not open JPA EntityManager for transaction; nested exception is org.hibernate.exception.JDBCConnectionException: Unable to acquire JDBC Connection
Caused by: org.hibernate.exception.JDBCConnectionException: Unable to acquire JDBC Connection
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException:
Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
Caused by: java.net.UnknownHostException: mysql
When running local test, they all passed, maven test default setting provided by IntelliJ IDEA is used.
Since the error complains about database connection, so I checked by Jenkins Audit to Database Plugin. Connection Successful!
The connection parameter in my application.properties also corresponds to this
spring.datasource.url=jdbc:mysql://mysql:3306/database?useLegacyDatetimeCode=false&serverTimezone=Asia/Shanghai
spring.datasource.username=root
spring.datasource.password=password
spring.datasource.maxActive=5
The MySQL in the URL is the MySQL docker container name. If change it with localhost or private IP in docker container inspect mysql the error message is the same, while the Stacktrace is a little different on last two lines.
for localhost
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
Caused by: java.net.ConnectException: Connection refused (Connection refused)
for private IP
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
Caused by: java.net.SocketTimeoutException: connect timed out
The different I think is the host in URL, localhost is used for the local test.
While the Jenkins server used Docker bridge network.
The container status is:
docker container ls
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS
NAMES
51ea7c7864a4 mysql:5.7 "docker-entrypoint.s…" 19 hours ago Up 19 hours 0.0.0.0:3306->3306/tcp mysql
de364f7b5eaf maven:3-jdk-8 "/usr/local/bin/mvn-…" 21 hours ago Up 21 hours
optimistic_stallman
a6545591e358 jenkinsci/blueocean "/sbin/tini -- /usr/…" 43 hours ago Up 43 hours 0.0.0.0:50000->50000/tcp, 0.0.0.0:2048->8080/tcp frosty_cray
When I run the JUnit test in IntelliJ, it fails sometimes on the local environment. The error log is like:
Caused by: org.h2.jdbc.JdbcSQLException: Schema "DATABASE" not found; SQL statement:
TRUNCATE TABLE database.data_log
I have searched the issue, it's said h2 database use upper case by default.
After run maven test, this issue will go if run JUnit test in IDE again. But this should be not related to the root cause.
Search on the error message, find some similar question but with different nested exception:
Could not open JPA EntityManager for transaction; nested exception is javax.persistence.PersistenceException
SpingREST: Could not open JPA EntityManager for transaction; nested exception is org.hiberna
Could not open JPA EntityManager for transaction; org.hibernate.exception.GenericJDBCException: Could not open connection
Could not open JPA EntityManager for transaction in spring
All of them is about nested exception is javax.persistence.PersistenceException
But nested exception is org.hibernate.exception.JDBCConnectionException: is my situation.
Read Connect Java to a MySQL database
however since that plugin connects OK, means the connection from Jenkins container to MySQL container is fine.
Summarise:
1. local test with maven passed
2. Jenkins plugin connect to MySQL success
3. Integration test fails when run from Jenkins
4. local test environment is WIN10 64bit; Jenkins run in docker container on Ubuntu 16.04 64bit server, with MySQL 5.7 container connects to the same bridge network.
Thanks to #rohit-thomas. We narrow down the question to something related to the host of the URL.
The simple answer is changing the host of the JDBC URL in the spring boot application.properties to the docker host IP address. From
spring.datasource.url=jdbc:mysql://mysql:3306/database?
to
spring.datasource.url=jdbc:mysql://172.17.0.1:3306/database?
From inside of a Docker container, how do I connect to the localhost of the machine?
This post also helps as the final solution.
ip addr show docker0
4: docker0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
...
inet 172.17.0.1/16 brd 172.17.255.255 scope global docker0
...
My conclusion is:
The Jenkins container builds from an image is able to communicate with the MySQL container with its container name or private address on docker bridge network. However, as the application built by the Jenkins is not able to do that.
Since the MySQL container port has bound to the host machine, the application could communicate with MySQL container through the host port.
If the conclusion is wrong, comments are welcome.
Some things you can check that might help you resolve this issue.
In application.properties try to use docker host IP address.
from
spring.datasource.url = jdbc:mysql://mysql:3306/DATABASE_URI_PATH
to
spring.datasource.url = jdbc:mysql://192.168.99.100:33060/DATABASE_URI_PATH
Note:
You will need to map your IP and port when you do docker run or ports in docker file.And use the same docker network among your containers.
Verify if you server app can reach your mysql or vice versa. Go inside the docker container and try to ping.
I am trying to host MySQL database on 1nd1.com. I have created a database with few tables. Getting below error while connecting to 1and1 database from java application.
When pinging from the command prompt using "ping hostname" command, getting a failure in response.
Is there any way to connect to this host from java program?
com.mysql.jdbc.CommunicationsException: Communications link failure due to underlying exception:
** BEGIN NESTED EXCEPTION **
java.net.UnknownHostException
MESSAGE: db726853948.db.1and1.com
STACKTRACE:
java.net.UnknownHostException: db726853948.db.1and1.com
at java.net.Inet6AddressImpl.lookupAllHostAddr(Native Method)
at java.net.InetAddress$2.lookupAllHostAddr(InetAddress.java:907)
at java.net.InetAddress.getAddressesFromNameService(InetAddress.java:1302)
at java.net.InetAddress.getAllByName0(InetAddress.java:1255)
at java.net.InetAddress.getAllByName(InetAddress.java:1171)
at java.net.InetAddress.getAllByName(InetAddress.java:1105)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:246)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:271)
at com.mysql.jdbc.Connection.createNewIO(Connection.java:2771)
at com.mysql.jdbc.Connection.<init>(Connection.java:1555)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:285)
at java.sql.DriverManager.getConnection(DriverManager.java:664)
at java.sql.DriverManager.getConnection(DriverManager.java:247)
at Contct.insertDetails(Contct.java:11)
at Contct.main(Contct.java:28)
** END NESTED EXCEPTION **
Last packet sent to the server was 0 ms ago.
try adding your hostname to your host file
for example:
your_host_ip(122.2.2.1) hostname(db726853948.db.1and1.com)
when i run my code, i get this exception:
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1121)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:357)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2482)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2519)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2304)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:834)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:416)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:346)
at java.sql.DriverManager.getConnection(DriverManager.java:664)
at java.sql.DriverManager.getConnection(DriverManager.java:208)
at org.springframework.jdbc.datasource.DriverManagerDataSource.getConnectionFromDriverManager(DriverManagerDataSource.java:153)
at org.springframework.jdbc.datasource.DriverManagerDataSource.getConnectionFromDriver(DriverManagerDataSource.java:144)
at org.springframework.jdbc.datasource.AbstractDriverBasedDataSource.getConnectionFromDriver(AbstractDriverBasedDataSource.java:155)
at org.springframework.jdbc.datasource.AbstractDriverBasedDataSource.getConnection(AbstractDriverBasedDataSource.java:120)
at org.hibernate.engine.jdbc.connections.internal.DatasourceConnectionProviderImpl.getConnection(DatasourceConnectionProviderImpl.java:139)
at org.hibernate.tool.hbm2ddl.SuppliedConnectionProviderConnectionHelper.prepare(SuppliedConnectionProviderConnectionHelper.java:51)
at org.hibernate.tool.hbm2ddl.DatabaseExporter.<init>(DatabaseExporter.java:52)
at org.hibernate.tool.hbm2ddl.SchemaExport.execute(SchemaExport.java:367)
at org.hibernate.tool.hbm2ddl.SchemaExport.create(SchemaExport.java:304)
at org.hibernate.tool.hbm2ddl.SchemaExport.create(SchemaExport.java:293)
at org.hibernate.internal.SessionFactoryImpl.<init>(SessionFactoryImpl.java:517)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1857)
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
Aug 25, 2015 8:23:45 PM com.sun.jersey.spi.container.ContainerResponse mapMappableContainerException
SCHWERWIEGEND: The RuntimeException could not be mapped to a response, re-throwing to the HTTP container
org.springframework.transaction.CannotCreateTransactionException: Could not open JPA EntityManager for transaction; nested exception is javax.persistence.PersistenceException: org.hibernate.exception.JDBCConnectionException: Could not open connection
at org.springframework.orm.jpa.JpaTransactionManager.doBegin(JpaTransactionManager.java:431)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.getTransaction(AbstractPlatformTransactionManager.java:373)
at org.springframework.transaction.interceptor.TransactionAspectSupport.createTransactionIfNecessary(TransactionAspectSupport.java:457)
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:276)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207)
at com.sun.proxy.$Proxy76.create(Unknown Source)
I don't know where is the problem. But yesterday i worked fine.
my database.properties:
jdbc.driverClassName=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/streaming
jdbc.username=root
jdbc.password=password
hibernate.dialect=org.hibernate.dialect.MySQLDialect
hibernate.showsql=true
hibernate.hbm2ddl.auto=create
It is possible for me to run mysql directly from command line. Where is the problem? Was is wrong.
I use spring 4 and hibernate with mysql as database language.
Has someone any ideas?
Thank.
There is CommunicationsException: Communications link failure.
If you get a SQLException: Connection refused or Connection timed out or a MySQL specific
CommunicationsException: Communications link failure
then it means that the DB isn't reachable at all. This can have one or more of the following causes:
IP address or hostname in JDBC URL is wrong.
Hostname in JDBC URL is not recognized by local DNS server.
Port number is missing or wrong in JDBC URL.
DB server is down.
DB server doesn't accept TCP/IP connections.
DB server has run out of connections.
Something in between Java and DB is blocking connections, e.g. a firewall or proxy.
To solve the one or the other, follow the following advices:
Verify and test them with ping.
Refresh DNS or use IP address in JDBC URL instead.
Verify it based on my.cnf of MySQL DB.
Start the DB.
Verify if mysqld is started without the --skip-networking option.
Restart the DB and fix your code accordingly that it closes connections in finally.
Disable firewall and/or configure firewall/proxy to allow/forward the port.
Source: More Details
I see that #Amit Tamrakar have good answer but I want to add:
if you make a lot of requests to db, (I mean connections), may be that application (some app thread) just wait for use free connection from app db connection pool, but throws timeout exception.
.h.engine.jdbc.spi.SqlExceptionHelper : HikariPool-1 - Connection is not available, request timed out after 30005ms.
Could not open JPA EntityManager for transaction; nested exception is org.hibernate.exception.JDBCConnectionException: Unable to acquire JDBC Connection
You can try to increase db connection pool in application config file, for example:
spring.datasource.hikari.maximum-pool-size=20
You can set size which you need. This config in app by default is 8.
And we need remember that each db have own free db connection size which we don't need exceed.
I mean if db have 5 free connection and you want to use 10 connections in your app then we will receive so exceptions.
DB is down.
You must start the DB server and check connectivity with either telnet or mysql command line client first.
I was not unable to figure out the exact cause, but I realized that it was because of some thread pools since I was able to connect to the db using the terminal.
for checking the connectivity you can use the below command.
psql -h hostname -U username -d database
so restarting the server worked for me.
I hosted my first Java EE web site but my mySQL connections are timing out after few minutes and I am getting this error message:
HTTP Status 500 - com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
type Exception report
message com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
description The server encountered an internal error that prevented it from fulfilling this request.
exception
dao.DAOException: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
Last packet sent to the server was 0 ms ago.
dao.OffreDaoImpl.lister(OffreDaoImpl.java:95)
filters.PrechargementFilter.doFilter(PrechargementFilter.java:96)
org.apache.catalina.filters.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:108)
root cause
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
Last packet sent to the server was 0 ms ago.
sun.reflect.GeneratedConstructorAccessor28.newInstance(Unknown Source)
sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
java.lang.reflect.Constructor.newInstance(Constructor.java:525)
com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074)
com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2985)
com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2871)
com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3414)
com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1936)
com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2060)
com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2542)
com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1734)
com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1885)
com.jolbox.bonecp.PreparedStatementHandle.executeQuery(PreparedStatementHandle.java:172)
dao.OffreDaoImpl.lister(OffreDaoImpl.java:90)
filters.PrechargementFilter.doFilter(PrechargementFilter.java:96)
org.apache.catalina.filters.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:108)
root cause
java.io.EOFException: Can not read response from server. Expected to read 4 bytes, read 0 bytes before connection was unexpectedly lost.
com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:2431)
com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2882)
com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2871)
com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3414)
com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1936)
com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2060)
com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2542)
com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1734)
com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1885)
com.jolbox.bonecp.PreparedStatementHandle.executeQuery(PreparedStatementHandle.java:172)
dao.OffreDaoImpl.lister(OffreDaoImpl.java:90)
filters.PrechargementFilter.doFilter(PrechargementFilter.java:96)
org.apache.catalina.filters.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:108)
I asked my hoster to increase the timeout value and here is his response:
Please accept our sincerest apologizes for misunderstanding.
Unfortunately due to shared hosting environment your request could not be >accomplished - it will affect other customers, that share server resources >for you. (10 min is max value for this parameter).
Since you strongly need some features - we can only suggest you considering >to move to VPS or dedicated server where you will have full admin >privileges and can do whatever you want without affecting of another >customers.
As a solution, we would like to suggest you to add in your jdbc connection >string following command:
&autoReconnect=true&failOverReadOnly=false&maxReconnects=10
In this case, after timeout, you will be reconnected again.
So I edited my config.properties file:
url = jdbc:mysql://localhost:3306/myDatabase&autoReconnect=true&failOverReadOnly=false&maxReconnects=10
driver = com.mysql.jdbc.Driver
username = xxxxxx
password = xxxxxx
But I am still facing the same issue.
Yes I am using localhost even when I host the website. But I tried to replace localhost string by the server address IP in the URL connection and I got this error message:
Caused by: java.sql.SQLException: Unable to open a test connection to the given database. JDBC url = jdbc:mysql://xxx.xxx.xxx.xx:3306/database_db?autoReconnect=true&failOverReadOnly=false&maxReconnects=10, username = user_name. Terminating connection pool. Original Exception: ------
com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 10 times. Giving up.
So I noted the issue to my hoster and here is his reply:
Dear Customer,
Kindly use localhost instead IP address, as for your string, we actually asking you to not maintain connections as long as you wish. The thing is we have hard limit on opened connections overall = 300 and 50 per user.
And as this is shared server these connections are being allocated on demand to each user, and if your account consumes 50 connections it is 1/6 of all connections available.