Authentication Error on Private Endpoint for Blob Storage

Hi there Nana Poku

Thanks for using QandA platform

This happens because with a private endpoint, all traffic must stay inside your private network, public access won't work unless DNS points to the private IP. If your DNS still resolves to the public IP, authentication will fail. you should have a Private DNS Zone (like privatelink.blob.core.windows.net) linked to your VNet, and your client is picking up the private IP. Also, it's better to use Azure AD for authentication instead of keys, also xheck your fireewall rules

If this helps kindly accept the answer thanks much.

Hi Nana Poku ,

The issue is specifically related to the authentication when switching from public access to private endpoint access. some additional steps to resolve,

Ensure that the DNS resolution for the Blob Storage account is correctly configured to resolve to the private endpoint's IP address. You can update the host file on your client machine or use a custom DNS server

Verify that the network security settings, including firewall rules and virtual network configurations, allow communication between your client and the Blob Storage via the private endpoint

check that the identity (managed identity or service principal) used for authentication has the necessary permissions, such as "Storage Blob Data Contributor" or "Storage Blob Data Owner"

If you are using Azure Storage Explorer, make sure it's configured to connect via the private endpoint. This may involve specific setup steps depending on the error message you're encountering.

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