readWriteSplitting plugin is unable to connect to reader host if enabled iam authentication

[smaliebsco]

Describe the bug

readWriteSplitting plugin works fine with master username and password but fails to connect reader instance with IAM authentication plugging. It falls back to the writer's instance and the application works by redirecting all the queries to writer's instance

Getting error as

    The plugin was unable to establish a reader connection to any reader instance.
    Failed to switch to a reader. The plugin was unable to establish a reader connection to any reader instance.. The current writer will be used as a fallback

I am using Spring and below are the datasource configs:

    hikari:
      data-source-properties:
        autoSortWrapperPluginOrder: true
        wrapperPlugins: iam,readWriteSplitting,failover,efm,auroraConnectionTracker,initialConnection
        wrapperDialect: aurora-mysql
        readerHostSelectorStrategy: random # is configured only for internal pooling
        readerInitialConnectionHostSelectorStrategy: random
        dynamicHostListProvider: com.amazonaws.jdbc.AwsWrapperDataSource

and using the @Trasactional(readOnly=true)

It seems I have the right policy configured for IAM authenticate rds-connect as its able to establish the connection with writer intance.

Expected Behavior

It should be able to connect to reader instances and redirect queries to the reader

What plugins are used? What other connection properties were set?

iam,readWriteSplitting,failover,efm,auroraConnectionTracker,initialConnection

Current Behavior

The plugin was unable to establish a reader connection to any reader instance.

Failed to switch to a reader. The plugin was unable to establish a reader connection to any reader instance.. The current writer will be used as a fallback

"software.amazon.jdbc.plugin.readwritesplitting.ReadWriteSplittingPlugin","message":"Failed to switch to a reader. The plugin was unable to establish a reader connection to any reader instance.. The current writer will be used as a fallback:

Reproduction Steps

configure the iam, and readwritesplit plugin with 1 reader and 1 writer instance and try to redirect to the reader using the annotation

@transactional(readOnly=true)

Possible Solution

No response

Additional Information/Context

No response

The AWS Advanced JDBC Driver version used

2.5.4

JDK version used

17

Operating System and version

Docker

[smaliebsco]

With these plugins its working fine:
iam,readWriteSplitting,failover,efm2

[aaron-congo]

Hi @smaliebsco,

Thanks for reaching out and raising this issue. We'll take a look at this and keep you updated as we investigate. Thank you for your patience!

[sergiyvamz]

Hi @smaliebsco

In order to troubleshoot your issue, could you provide more details?

• Do you use Aurora writer endpoints (<cluster>.cluster-<XYZ>.<region>.rds.amazonaws.com) or
  similar cluster reader endpoint or an instance endpoint to connect to the database? Or, do you use custom domain (CNAME alias) that points to an Aurora endpoint?

• Could you provide driver logs for package software.amazon.jdbc that covers a longer timeline? That helps to troubleshoot the issue. You can find more details about logging here:
  https://github.com/aws/aws-advanced-jdbc-wrapper/blob/main/docs/using-the-jdbc-driver/UsingTheJdbcDriver.md#logging

I also see that you use dynamicHostListProvider parameter in your configuration. This parameter doesn't exist in the driver and you can remove this parameter (unless you need it for some other purposes).

[sergiyvamz]

Hi @smaliebsco

Since we haven’t seen a response, we will close this ticket for now. However, if the issue isn't resolved, you can reopen this issue, or create a new one. Please include additional details as requested.

Thank you!