Anomaly storage Growth on Azure PostgreSQL Single Server Primary

Question

Dear all,

I am currently experiencing a critical issue with my Azure PostgreSQL deployment.

I have a primary and read replica configuration, and I've noticed a rapid growth in storage without any changes applied from my side. Despite thorough investigations, I am unable to identify the root cause. Here are the steps I've taken so far:

Table Analysis:

Checked tables on both servers and found no anomalies.

The combined size of tables on both servers is 52GB, but the used storage metrics indicate almost 80 GB.

Reboot Attempt:

Rebooted both servers, but the issue persists.

Log Analysis:

Primary server logs don't contain any suspicious information.

Replica server logs indicate the following error:

2023-12-20 06:42:19 UTC-65828cca.1c0-FATAL: could not connect to the primary server: SSL error: tlsv1 alert unknown ca.  

Considering the SSL error, I suspect this might be related to certificate rotation performed by Azure. If so, how can I workaround this issue, especially if I am unable to import a new CA certificate to the Azure PostgreSQL Single Server Replica instance?

Any help in further investigation will be appreciated!

--

Thanks,

Oles

Answer 1

Hi
Oleksandr Ridkodub •,

I'm glad that you were able to resolve your issue and thank you for posting your solution so that others experiencing the same thing can easily reference this! Since the Microsoft Q&A community has a policy that "The question author cannot accept their own answer. They can only accept answers by others (Opens in new window or tab)", I'll repost your solution in case you'd like to "Accept (Opens in new window or tab)" the answer.

Solution:

The storage issue on primary was fixed immediately after the read replica was re-created.

If you have any other questions or are still running into more issues, please let me know.
Thank you again for your time and patience throughout this issue.

Please remember to "Accept Answer" if any answer/reply helped, so that others in the community facing similar issues can easily find the solution.

Answer 2

Hi
Oleksandr Ridkodub •,

Welcome to Microsoft Q&A forum.

As I understand, you are getting Anomaly storage Growth on Azure PostgreSQL Single Server Primary.

We are sorry about the issue you are facing currently.

This problem looks strange and needs to be analyzed deeply.

I would recommend you to please file a support ticket for deeper investigation and in case if you don't have a support plan, do let us know here so that we can check on other options to unblock you.

Thanks

Answer 3

Hello @Oleksandr Ridkodub

I am glad that you have resolved an issue with SQL Replica storage

Error tlsv1 alert unknown ca means that postgres was not able to validate the SSL certificate. If SSL mode is enabled in your Azure Postgres you need to use CA chain to connect to your DB
I may missing one of the CA certificates in the chain. Try to append the missing CA certificate to the CA file you are using.

https://learn.microsoft.com/en-us/azure/postgresql/single-server/concepts-certificate-rotation