Hello @Mayank Sharma
Thank you for reaching out to the Microsoft Q&A platform.
In VMSS SKU upgrade, the existing public IP and private IP for existing VMs are maintained. The upgrade process does not affect the IP addresses of the VMs in the scale set.
Regarding the issue with the Azure Log Analytics Connector and the Data Collection endpoint, if you have turned off public access to the endpoint, you will need to use a private endpoint to send data to your log analytics workspace.
Since you have regional VNet integration and can reach the private endpoints, you can set up a private endpoint for Azure Monitor and update your logic app to use the private endpoint instead of the Data Collection endpoint. This will allow you to securely send data to your log analytics workspace without exposing the Data Collection endpoint to the public internet.
To set up a private endpoint for Azure Monitor, you can follow the steps outlined in the Azure Monitor documentation. Once you have set up the private endpoint, you can update your logic app to use the private endpoint instead of the Data Collection endpoint.
I hope this helps! Let me know if you have any further questions.
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