Re: BUG #16641: Postgresql driver 42.2.15 and 42.2.16 has problems connecting to AWS RDS Postgresql database

Hi Dave
Thank you for the feedback, that sounds very plausible.
I will file the bug with the AWS RDS team today. Good to know the default setting will change in the next release.

Flemming

Den 2. okt. 2020 kl. 01.05 skrev Dave Cramer <davecramer(at)postgres(dot)rocks>:



On Tue, 29 Sep 2020 at 06:16, PG Bug reporting form <noreply(at)postgresql(dot)org<mailto:noreply(at)postgresql(dot)org>> wrote:
The following bug has been logged on the website:

Bug reference: 16641
Logged by: Flemming Jønsson
Email address: frjtrifork(at)gmail(dot)com<mailto:frjtrifork(at)gmail(dot)com>
PostgreSQL version: 10.7
Operating system: AWS RDS Serverless
Description:

I have a Spring Boot application in production in AWS Elastic Container
Service.

With Spring Boot 2.3.3 the postgresql driver 42.2.14 is used and the
application connects without issues to the AWS RDS serverless postgresql
10.7 engine.
I know you support 10.14 currently, but 10.7 is the latest postgresql
version that can be configured in RDS serverless - so I'm hoping it is ok to
file this issue.

After upgrading to Spring Boot 2.3.4 the postgresql driver 42.2.16 was
included and our application could no longer connect to RDS.
We consistently get this stacktrace on startup with 42.2.16 (for the record
42.2.15 seem to produce the same stacktrace):

Caused by: org.flywaydb.core.internal.exception.FlywaySqlException:
--
| Unable to obtain connection from database: The connection attempt
failed.
|
-------------------------------------------------------------------------
| SQL State : 08001
| Error Code : 0
| Message : The connection attempt failed.
| at
org.flywaydb.core.internal.jdbc.JdbcUtils.openConnection(JdbcUtils.java:65)
~[flyway-core-6.4.4.jar:na]
| at
org.flywaydb.core.internal.jdbc.JdbcConnectionFactory.<init>(JdbcConnectionFactory.java:80)
~[flyway-core-6.4.4.jar:na]
| at org.flywaydb.core.Flyway.execute(Flyway.java:456)
~[flyway-core-6.4.4.jar:na]
| at org.flywaydb.core.Flyway.migrate(Flyway.java:159)
~[flyway-core-6.4.4.jar:na]
| at
org.springframework.boot.autoconfigure.flyway.FlywayMigrationInitializer.afterPropertiesSet(FlywayMigrationInitializer.java:65)
~[spring-boot-autoconfigure-2.3.4.RELEASE.jar:2.3.4.RELEASE]
| at
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1853)
~[spring-beans-5.2.9.RELEASE.jar:5.2.9.RELEASE]
| at
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1790)
~[spring-beans-5.2.9.RELEASE.jar:5.2.9.RELEASE]
| ... 27 common frames omitted
| Caused by: org.postgresql.util.PSQLException: The connection attempt
failed.
| at
org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:315)
~[postgresql-42.2.16.jar:42.2.16]
| at
org.postgresql.core.ConnectionFactory.openConnection(ConnectionFactory.java:51)
~[postgresql-42.2.16.jar:42.2.16]
| at org.postgresql.jdbc.PgConnection.<init>(PgConnection.java:225)
~[postgresql-42.2.16.jar:42.2.16]
| at org.postgresql.Driver.makeConnection(Driver.java:465)
~[postgresql-42.2.16.jar:42.2.16]
| at org.postgresql.Driver.connect(Driver.java:264)
~[postgresql-42.2.16.jar:42.2.16]
| at
com.zaxxer.hikari.util.DriverDataSource.getConnection(DriverDataSource.java:138)
~[HikariCP-3.4.5.jar:na]
| at com.zaxxer.hikari.pool.PoolBase.newConnection(PoolBase.java:358)
~[HikariCP-3.4.5.jar:na]
| at com.zaxxer.hikari.pool.PoolBase.newPoolEntry(PoolBase.java:206)
~[HikariCP-3.4.5.jar:na]
| at
com.zaxxer.hikari.pool.HikariPool.createPoolEntry(HikariPool.java:477)
~[HikariCP-3.4.5.jar:na]
| at com.zaxxer.hikari.pool.HikariPool.checkFailFast(HikariPool.java:560)
~[HikariCP-3.4.5.jar:na]
| at com.zaxxer.hikari.pool.HikariPool.<init>(HikariPool.java:115)
~[HikariCP-3.4.5.jar:na]
| at
com.zaxxer.hikari.HikariDataSource.getConnection(HikariDataSource.java:112)
~[HikariCP-3.4.5.jar:na]
| at
org.flywaydb.core.internal.jdbc.JdbcUtils.openConnection(JdbcUtils.java:56)
~[flyway-core-6.4.4.jar:na]
| ... 33 common frames omitted
| Caused by: java.io.EOFException: null
| at org.postgresql.core.PGStream.receiveChar(PGStream.java:443)
~[postgresql-42.2.16.jar:42.2.16]
| at
org.postgresql.core.v3.ConnectionFactoryImpl.enableGSSEncrypted(ConnectionFactoryImpl.java:436)
~[postgresql-42.2.16.jar:42.2.16]
| at
org.postgresql.core.v3.ConnectionFactoryImpl.tryConnect(ConnectionFactoryImpl.java:144)
~[postgresql-42.2.16.jar:42.2.16]
| at
org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:213)
~[postgresql-42.2.16.jar:42.2.16]
| ... 45 common frames omitted

If I upgrade to Spring Boot 2.3.4 and force the postgresql driver to stay at
42.2.14 our application works nicely in AWS ECS and connects to the
serverless RDS Postgresql database without problems.
I filed a workaround for Spring Boot maven in the Spring Boot issue tracker
here https://github.com/spring-projects/spring-boot/issues/23523

Is this above stack trace a known feature when gssEncMode=disabl the latest driver
against RDS serverless that is 'stuck' at 10.7 engine - or is it something
that can be fixed?

/Flemming

Well the problem is that the driver attempts to make a GSS encrypted connection and AWS doesn't adhere to the PostgreSQL protocol.

You can add gssEncMode=disable to the connection and the driver will not attempt the encrypted connection.
We will be releasing shortly a version which does not default to attempting the gssEncMode.
You really should be filing this but with Amazon as their product does not adhere to the PostgreSQL protocol

Dave