Hi @Johnm,
Welcome to the Microsoft Q&A Platform! Thank you for asking your question here.
We would like to inform you that, when you create a new server in Azure SQL Database a server-level firewall blocks all access to the public endpoint for the server. Connection attempts from the internet and Azure must pass through the firewall before they reach your server or database. Firewall rules can be of two types Server-level IP firewall rules and Database-level IP firewall rules.
Azure SQL Database creates a firewall at the server level for single and pooled databases. This firewall blocks connections from IP addresses that do not have permission. To connect to an Azure SQL database from an IP address outside of Azure, you need to create a firewall rule. You can use rules to open a firewall for a specific IP address or for a range of IP addresses.
Note:
- Azure SQL Database communicates over port 1433. When you connect from within a corporate network, outbound traffic over port 1433 might not be permitted by your network firewall. This means your IT department needs to open port 1433 for you to connect to your server.
- A firewall rule of 0.0.0.0 enables all Azure services to pass through the server-level firewall rule and attempt to connect to a database through the server.
Please refer to the below mentioned links for more information.
https://learn.microsoft.com/en-us/azure/firewall-manager/policy-overview
I hope, This response will address your query and helped you to overcome on your challenges.
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