报错信息

2023-03-02 14:59:42.624  WARN 13506 --- [HelperThread-#1] c.m.v.r.BasicResourcePool                : com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask@1cbc5521 -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (30). Last acquisition attempt exception:

org.postgresql.util.PSQLException: ��������: û���������� "xx.xx.xxx.xx", �û� "postgres", ���ݿ� "test", SSL �ر� �� pg_hba.conf ��¼
        at org.postgresql.core.v3.ConnectionFactoryImpl.doAuthentication(ConnectionFactoryImpl.java:659) ~[postgresql-42.5.0.jar!/:42.5.0]
        at org.postgresql.core.v3.ConnectionFactoryImpl.tryConnect(ConnectionFactoryImpl.java:180) ~[postgresql-42.5.0.jar!/:42.5.0]
        at org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:235) ~[postgresql-42.5.0.jar!/:42.5.0]
        at org.postgresql.core.ConnectionFactory.openConnection(ConnectionFactory.java:49) ~[postgresql-42.5.0.jar!/:42.5.0]
        at org.postgresql.jdbc.PgConnection.<init>(PgConnection.java:247) ~[postgresql-42.5.0.jar!/:42.5.0]
        at org.postgresql.Driver.makeConnection(Driver.java:434) ~[postgresql-42.5.0.jar!/:42.5.0]
        at org.postgresql.Driver.connect(Driver.java:291) ~[postgresql-42.5.0.jar!/:42.5.0]
        at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:175) ~[c3p0-0.9.5.5.jar!/:0.9.5.5]
        at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:220) ~[c3p0-0.9.5.5.jar!/:0.9.5.5]
        at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:206) ~[c3p0-0.9.5.5.jar!/:0.9.5.5]
        at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:203) ~[c3p0-0.9.5.5.jar!/:0.9.5.5]
        at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1176) ~[c3p0-0.9.5.5.jar!/:0.9.5.5]
        at com.mchange.v2.resourcepool.BasicResourcePool.doAcquireAndDecrementPendingAcquiresWithinLockOnSuccess(BasicResourcePool.java:1163) ~[c3p0-0.9.5.5.jar!/:0.9.5.5]
        at com.mchange.v2.resourcepool.BasicResourcePool.access$700(BasicResourcePool.java:44) ~[c3p0-0.9.5.5.jar!/:0.9.5.5]
        at com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask.run(BasicResourcePool.java:1908) ~[c3p0-0.9.5.5.jar!/:0.9.5.5]
        at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:696) ~[mchange-commons-java-0.2.19.jar!/:0.2.19]
        Suppressed: org.postgresql.util.PSQLException: ��������: û���������� "xx.xx.xxx.xx", �û� "postgres", ���ݿ� "test", SSL �ر� �� pg_hba.conf ��¼
                at org.postgresql.core.v3.ConnectionFactoryImpl.doAuthentication(ConnectionFactoryImpl.java:659) ~[postgresql-42.5.0.jar!/:42.5.0]
                at org.postgresql.core.v3.ConnectionFactoryImpl.tryConnect(ConnectionFactoryImpl.java:180) ~[postgresql-42.5.0.jar!/:42.5.0]
                at org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:244) ~[postgresql-42.5.0.jar!/:42.5.0]
                at org.postgresql.core.ConnectionFactory.openConnection(ConnectionFactory.java:49) ~[postgresql-42.5.0.jar!/:42.5.0]
                at org.postgresql.jdbc.PgConnection.<init>(PgConnection.java:247) ~[postgresql-42.5.0.jar!/:42.5.0]
                at org.postgresql.Driver.makeConnection(Driver.java:434) ~[postgresql-42.5.0.jar!/:42.5.0]
                at org.postgresql.Driver.connect(Driver.java:291) ~[postgresql-42.5.0.jar!/:42.5.0]
                at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:175) ~[c3p0-0.9.5.5.jar!/:0.9.5.5]
                at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:220) ~[c3p0-0.9.5.5.jar!/:0.9.5.5]
                at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:206) ~[c3p0-0.9.5.5.jar!/:0.9.5.5]
                at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:203) ~[c3p0-0.9.5.5.jar!/:0.9.5.5]
                at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1176) ~[c3p0-0.9.5.5.jar!/:0.9.5.5]
                at com.mchange.v2.resourcepool.BasicResourcePool.doAcquireAndDecrementPendingAcquiresWithinLockOnSuccess(BasicResourcePool.java:1163) ~[c3p0-0.9.5.5.jar!/:0.9.5.5]
                at com.mchange.v2.resourcepool.BasicResourcePool.access$700(BasicResourcePool.java:44) ~[c3p0-0.9.5.5.jar!/:0.9.5.5]
                at com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask.run(BasicResourcePool.java:1908) ~[c3p0-0.9.5.5.jar!/:0.9.5.5]
                at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:696) ~[mchange-commons-java-0.2.19.jar!/:0.2.19]

2023-03-02 14:59:42.625  WARN 13506 --- [HelperThread-#1] c.m.v.r.BasicResourcePool                : Having failed to acquire a resource, com.mchange.v2.resourcepool.BasicResourcePool@7b36a430 is interrupting all Threads waiting on a resource to check out. Will try again in response to new client requests.

背景

在本地电脑写好了一个springboot + mybatis + pg的项目，在本地调试运行正常，将项目打成jar包在服务器上运行，当与pg交互时出现上述报错信息。

原因

当前服务器ip不在pg数据库允许访问的范围内

解决方式

1）找到pg的安装路径，该路径下有个data文件夹，在data文件夹找到pg_hba.conf配置文件
2）打开pg_hba.conf配置文件，在ipv4下添加服务器ip，例如

# TYPE   DATABASE        USER            ADDRESS                 METHOD
   host      all                       all                 10.10.56.17/32             md5

上述表示允许IP地址为10.10.56.17的所有用户可以通过MD5的密码验证方式连接主机上所有的数据库。
3）修改后保存，打开pg终端，执行pg_ctl reload，使配置生效。

至此，可正常连接pg数据库。