Why isn't the wrapper plug-in named 'initialConnection' described?

[LowestYJ]

I saw this page what introducing wrapper driver for Amazon Aurora.
(https://aws.amazon.com/ko/blogs/database/introducing-the-advanced-jdbc-wrapper-driver-for-amazon-aurora/)
Our team is going to apply this wrapper into our Spring projects for respond to failover.
But why isn't write the plug-in named 'initialConnection' specified on the site?
Does it work normally without the corresponding plug-in?

[karenc-bq]

Hi @LowestYJ, the initialConnection plugin refers to the Aurora Initial Strategy Connection Plugin, you can learn more about it from our Github documentation.

This plugin is not required for failover, but may be helpful. Could you please tell us more about your use case so we can help you determine whether this plugin is good add-on or an overhead for your application?

[LowestYJ]

Hi @karenc-bq, thanks for your response 😄
Our application server is using aurora mysql.
We are going to use aws-advanced-jdbc-wrapper for the purpose of responding to sudden failover situations.
I'm looking forward to the effect of finding and connecting the writer and reader node that change in the failover situation if I use the aws-advanced-jdbc-wrapper.
I was wondering if I would need an 'initialConnection' plug-in for this kind of purpose.
And I want you to explain in detail what exactly 'may be helpful' means.

I'm also curious about the difference between using failover2, efm2 and using failover, efm (version1).

[karenc-bq]

Hi @LowestYJ, we recommend starting with the default list of plugins (auroraConnectionTracker,failover2,efm2) to handle failover scenarios.

To answer your questions:

1. Right after a server failover, the DNS may not be immediately up to date. If you're using a cluster endpoint, it may still point to a stale writer instance and the Aurora Initial Connection Strategy plugin can help alleviate this situation. However this feature is already included in the failover plugins by default, which is why this may not be useful for your application.
   The other functionality the Initial plugin has is selecting a reader instance based on the specified reader selection strategy. This is useful if you are frequently using the reader cluster endpoint.

2. Failover2 and EFM2 are both functionally equivalent to their predecessors. The version 2s aim to be more stable as they address some common issues reported by customers when they were using Failover and EFM. More details are provided here:

   • Failover2 vs Failover
   • EFM2