DBCP连接池连接MySql数据库时,一奇葩数据库设置为30秒内无请求自动断开.超时后链接无法关闭,活动链接数飞奔,最后挂掉. 网上找了一圈,一般是这三种,方法一pass,方法二测试无效可能设置错了吧,再者本身30秒已经够短了,最后落在了方法三, BasicDataSource ds = new BasicDataSource();          ds.setTimeBetweenEvictionRunsMillis(1000*20);        ds.setTestWhileIdle(…

前端时间到客户那去进行项目的上线测试,将项目部署好之后,运行都是正常的,可是每到了第二天早上访问的时候,就会报一个Could not open Hibernate session for transaction 异常,Caused by: com.mysql.jdbc.CommunicationsException: Communications link failure due to underlying exception,当时很摸不着头脑,后来就开始从数据库连接的源头开始找,本次项目中用的…

最近在用一个MySQL的Java连接池的过程中,连接一晚上不释放,第二天就会造成超时的错误,查了一下原因,原来是因为MySQL默认的空闲等待时间是8个小时,一旦空闲超过8个小时,就会抛出异常.异常文本如下: com.mysql.jdbc.CommunicationsException MESSAGE: Communications link failure due to underlying exception: ** BEGIN NESTED EXCEPTION ** java.net.Soc…

异常描述 这个异常通常有如下信息: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet successfully received from the server was 59,977 milliseconds ago. The last packet sent successfully to the server was 1 millisecon…

09:00:30.307 [http-8080-6] ERROR org.hibernate.transaction.JDBCTransaction -JDBC begin failed com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet successfully received from the server was 56,237,340 mi…

报错: MySQL第二天早上第一次连接超时报错, com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure 原因: 上述问题是由mysql5数据库的配置引起的.mysql5将其连接的等待时间(wait_timeout .interactive_timeout)缺省为8小时.在其客户程序中可以这样来查看其值: mysql> show global variables like 'wait…

现象:客户端连接服务器端mysql是没问题的,所有都木有问题,应用程序配置也没问题,但是连接就抛异常: 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 f…

感谢大佬:https://blog.csdn.net/a704397849/article/details/93797529 springboot + mybatis多数据库 + druid连接池配置成功.正常运行后,访问第一个数据库后访问第二个数据库,再去访问第一个数据库 会报错: Error querying database. Cause: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications lin…

很长的报错,截取   ERROR c.a.d.p.DruidDataSource - discard connection   com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure       The last packet successfully received from the server was 44,866 milliseconds ago. The last pac…

一.背景 最近在家里捣鼓一个公司自己搭建的demo的时候,发现程序一启动就会出现CommunicationsException: Communications link failure错误,经过一番排查最后发现是数据库url写错造成的,这个过程中也对出现这个错误的解决思路有了一些自己的理解,现和大家分享.该错误的具体信息如下: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure…

2019-11-22 17:15:27,705 FATAL [IPC Server handler 13 on 44844] org.apache.hadoop.mapred.TaskAttemptListenerImpl: Task: attempt_1574410493054_0011_m_000000_0 - exited : java.lang.RuntimeException: java.lang.RuntimeException: com.mysql.jdbc.exceptions.…

问题描述 App Service使用jdbc连接MySQL服务,出现大量的  Communications link failure: com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received…

-- 查询mysql 数据库链接空闲时间持有最大空闲时间,单位为秒 SHOW VARIABLES WHERE VAriable_name = 'interactive_timeout'; -- 会出现wait_timeout与该参数意思相近,修改时,一起修改 SHOW VARIABLES WHERE VAriable_name = '%timeout'; -- 解决问题 com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Commun…

不多说,直接上干货! 问题详情 [hadoop@bigdatamaster oozie--cdh5.5.4]$ bin/ooziedb.sh create -sqlfile oozie.sql -run DB Connection [hadoop@bigdatamaster oozie--cdh5.5.4]$ bin/ooziedb.sh create -sqlfile oozie.sql -run DB Connection setting CATALINA_OPTS="$CATALINA_O…

1.使用sqoop技术将mysql的数据导入到Hive出现的错误如下所示: 第一次使用命令如下所示: [hadoop@slaver1 sqoop--cdh5.3.6]$ bin/sqoop import --connect jdbc:mysql://localhost:3306/test --username root --password 123456 --table tb_user --hive-import --m 1 Warning: /home/hadoop/soft/sqoop--c…

数据库 没有开启  连接失败 org.apache.ibatis.exceptions.PersistenceException: ### Error querying database. Cause: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet sent successfully to the server was 0 milliseco…

最近在搞一个Spring boot + Mybatis + Mysql的项目,用Mybatis访问数据库时,报了如下的错误,先在网上搜索了,试了各种办法都不行, 奇葩的是,连接另外1个数据库又没问题.  最后发现是因为Mybatis的Mapper.xml文件中的SQL语句后面,多了个分号[;],导致SQL查询要等待很久,直到返回下面的报错. com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link f…

com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure 长时间没连接mysql断开了,重新启动就好了.…

现象: 报错:Exception in thread "main" com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure 解决办法: 更换 mysql-connector-java-8.0.11.jar 为 mysql-connector-java-8.0.16.jar, 下载位置:https://mvnrepository.com/artifact/mysql/mysql-c…

数据库连接失败 一.例如我在SpringBoot项目中使用了阿里的数据库连接池Driud. 有次在启动的时候,会报这样的错: Caused by: com.mysql.cj.exceptions.CJCommunicationsException: Communications link failure The last packet successfully received from the server was 319 milliseconds ago. The last packet s…

背景 使用sqoop从mysql导数据到hive,从本地服务器是可以访问mysql的(本地服务器是hadoop集群的一个datanode),但是sqoop导数据的时候依然连接不上mysql 报错如下: 从报错可以看出,是数据库连接失败,很常见的问题,但是从本地是可以直连mysql的. 因为sqoop导数据的时候,默认会启动4个map task,这4个map task会随机启动在不动的datanode上,所以在想,是不是因为其他节点没有权限访问mysql导致. 但是需要先搞清楚,sqoop在抽取数…

解决方案 连接Mysql报错 The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server. 检查mysql服务是否开启…

数据库服务没有开或者是驱动那块的问题…

1.首先检查生产环境的机器是否ping的通和telnet的通数据库 2.排查数据库连接的参数 3.看数据量是否很大 参考: http://blog.csdn.net/sclxf/article/details/5775125…

网上各式各样的问题,不过我的问题在于我开了Proxifier,导致链接localhost的时候被拦截...把Proxifier关了就好了 以后遇到这种问题.连不上数据库啊,连不上本地的服务器啊,先检查一下本机是否开了某种代理软件...…

这两天遇到一个mysql连接的问题,找人弄了好几天也没弄好,先看一下报错信息: ==================================================================== org.springframework.transaction.CannotCreateTransactionException: Could not open Hibernate Session for transaction; nested exception is org.h…

在使用JDBC连接mysql时可能会遇到以下错误: 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 解决方法: 将 Str…

问题现象 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. I spend some days to solve this…

一,异常现象 com.bill99.inf.ibatis.DBException: queryForList error::sqlId=orgOrderAssetsMapping.queryModelOrgOrderAssetsMapping param:com.bill99.boss.domain.org.model.OrderAssetsMapping@51ab0a47 at com.bill99.inf.ibatis.SqlMapDao.queryForList(SqlMapDao.jav…

# #错误日志 2016-11-10 16:19:20,834 ERROR [org.quartz.core.JobRunShell] - Job DEFAULT.jobtask threw an unhandled Exception: org.springframework.scheduling.quartz.JobMethodInvocationFailedException: Invocation of method 'execute' on target class [class co…