Aurora故障转移使连接以只读状态打开

Question

我们在Aurora集群中使用MySQL，我们有两个实例--主实例和从实例。我们在c3po连接池上处理spring事务。我们使用的是mariadb jdbc驱动程序（版本2.2.3)。

Caused by: org.springframework.jdbc.UncategorizedSQLException: PreparedStatementCallback; uncategorized SQLException for SQL [INSERT INTO a (a1, a2, a3, a4) VALUES (?, ?, ?, ?) on duplicate key update ]; SQL state [HY000]; error code [1290]; (conn=7) The MySQL server is running with the --read-only option so it cannot execute this statement; nested exception is java.sql.SQLException: (conn=7) The MySQL server is running with the --read-only option so it cannot execute this statement
    at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:84)
    at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:81)
    at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:81)
    at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:645)
    at org.springframework.jdbc.core.JdbcTemplate.update(JdbcTemplate.java:866)
    at org.springframework.jdbc.core.JdbcTemplate.update(JdbcTemplate.java:927)
    at org.springframework.jdbc.core.JdbcTemplate.update(JdbcTemplate.java:937)
    at com.persistence.impl.MyDao.insert(MyDao.java:52)
    at org.springframework.scheduling.quartz.QuartzJobBean.execute(QuartzJobBean.java:75)
    at org.quartz.core.JobRunShell.run(JobRunShell.java:213)
    ... 1 common frames omitted
Caused by: java.sql.SQLException: (conn=7) The MySQL server is running with the --read-only option so it cannot execute this statement
    at org.mariadb.jdbc.internal.util.exceptions.ExceptionMapper.get(ExceptionMapper.java:198)
    at org.mariadb.jdbc.internal.util.exceptions.ExceptionMapper.getException(ExceptionMapper.java:110)
    at org.mariadb.jdbc.MariaDbStatement.executeExceptionEpilogue(MariaDbStatement.java:228)
    at org.mariadb.jdbc.MariaDbPreparedStatementClient.executeInternal(MariaDbPreparedStatementClient.java:216)
    at org.mariadb.jdbc.MariaDbPreparedStatementClient.execute(MariaDbPreparedStatementClient.java:150)
    at org.mariadb.jdbc.MariaDbPreparedStatementClient.executeUpdate(MariaDbPreparedStatementClient.java:183)
    at com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.executeUpdate(NewProxyPreparedStatement.java:410)
    at org.springframework.jdbc.core.JdbcTemplate$2.doInPreparedStatement(JdbcTemplate.java:873)
    at org.springframework.jdbc.core.JdbcTemplate$2.doInPreparedStatement(JdbcTemplate.java:866)
    at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:629)
    ... 9 common frames omitted

Answer 1

我们通过实现一个ExceptionInterceptor来解决这个问题，在这个过程中，我们关闭了连接，迫使池创建一个新的连接。

此工作循环与mysql-connector-java 5.1.47相关

@Override
public SQLException interceptException(SQLException sqlEx, Connection conn) {
    if (sqlEx.getErrorCode() == READ_ONLY_ERROR_CODE) {
        log.warn("Got read only exception closing the connection {} ", sqlEx.getMessage());
        closeConnection(conn);
    }
    return sqlEx;
}