由于rds-combined-ca-bundle.pem包含一堆证书，如果我们拆分它们并为所有证书创建.pem文件并将它们分别导入到keystore，它将会起作用.

Since rds-combined-ca-bundle.pem contains a bunch of certificates, if we split them and create .pem files for all certificates and import them to keystore separately, it will work.

此问题是由于将整个rds证书捆绑包导入密钥库而引起的.

The problem is caused because of importing the entire rds certificate bundle to keystore.