.NET Connectivity to Oracle Autonomous Database Serverless

Recommended ODP.NET Versions

Oracle recommends using the latest ODP.NET 19c, which is the long term release.
Alternatively you may use the latest ODP.NET 21c if you require its new features. 21c is an innovation release.

Recent Changes to Oracle Autonomous Database Serverless (ADB-S) Connectivity

DigiCert retired the Organizational Unit (OU) field for all public TLS/SSL certificates to comply with industry standards as of August 2022 per their announcement. This means that the public TLS/SSL certificates issued by DigiCert will no longer have an OU field. Refer to My Oracle Support (MOS) note 2911553.1 for details.

To avoid disruption to applications connecting to Oracle ADB-S during the server side certificate change, .NET applications should use hostname based matching of the server certificate, i.e. .NET applications should be configured to match the server certificate based on the hostname used in the TNS connection string.

How to Ensure that Hostname Distinguished Name (DN) Matching Is On

  • (1) Recommended Releases: Use ODP.NET 21.9 or later or 19.18 or later. No other app changes are needed.
  • (2) If you require an older ODP.NET major version, use the download below. No other app changes are needed.
  • Additional Step Required if You Changed the TNS Connection String
    ADB-S connect strings contain hostname "...(HOST=xyz)..." which depends on the region. For example, in the Chicago region the hostname would be "adb.us-chicago-1.oraclecloud.com"). If you have replaced the default hostname with an IP address or a custom hostname, then hostname based DN matching will fail. The solution is to add a new entry to your /etc/hosts file using the original ADB-S domain suffix. The connection string should use this new name. For example an entry "localtunnel-adb.us-chicago-1.oraclecloud.com" could be created and used.

Additional Resources