PostgreSQL Major Version Upgrade Issues

Question

We have an issue upgrading Azure Database for PostgreSQL flexible server from version 14 to version 18.

We have followed the Major version upgrades in Azure Database for PostgreSQL guide.

The upgrade was attempted on a restored backup instance as suggested by the guide. The main issue is the lack of information on why the upgrade is failing.

The failure has a status of Conflict - An unexpected error occured while processing the request. Tracking ID: '9d955699-4f3a-405f-a9fa-2d1ba9f883fb' (Code: InternalServerError).

The operation details only show the following:

{
    "status": "Failed",
    "error": {
        "code": "InternalServerError",
        "message": "An unexpected error occured while processing the request. Tracking ID: '9d955699-4f3a-405f-a9fa-2d1ba9f883fb'"
    }
}

Getting more insights about why the upgrade fails is crucial. Please advise on how to continue and what additional information you need in order to identify and resolve the issue.

Answer 1

I think the shortest safe path is to try the upgrade once from a clean restore with all non‑default extensions and parameters removed, and when the same InternalServerError appears, the tracking ID has to go to Azure support because the detailed cause is only available on their side.

Answer 2

Hello Andrej Taneski,

Welcome to the Microsoft Q&A and thank you for posting your questions here.

I understand that you are having PostgreSQL Major Version Upgrade Issues.

The upgrade failure was caused by unsupported extensions and shared_preload_libraries configurations blocking Azure PostgreSQL Flexible Server prechecks for a major version upgrade.

The best practice and minimal-risk resolution is to:

• Remove unsupported preload libraries from shared_preload_libraries
• Remove or upgrade incompatible extensions
• Delete read replicas if present
• Ensure all pending maintenance operations are complete
• Retry the in-place major version upgrade using the Azure Portal or CLI

After removing unsupported preload libraries and incompatible extensions, the upgrade prechecks passed and the PostgreSQL major version upgrade completed successfully with minimal operational impact.

Use the below resource links for more reading and steps:

• https://learn.microsoft.com/azure/postgresql/flexible-server/concepts-major-version-upgrade
• https://learn.microsoft.com/azure/postgresql/flexible-server/how-to-perform-major-version-upgrade
• https://learn.microsoft.com/azure/postgresql/flexible-server/concepts-supported-versions
• https://techcommunity.microsoft.com/blog/adforpostgresql/major-version-upgrade-in-azure-postgresql-flexible-server---generally-available/3740913

I hope this is helpful! Do not hesitate to let me know if you have any other questions or clarifications.

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