Block ping and telnet Azure SQL database

Azure SQL Database blocks all inbound connections by default - so unless you explicitly allowed connections, there is no additional configuration required

More at https://zcusa.951200.xyz/en-us/azure/azure-sql/database/network-access-controls-overview?view=azuresql

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hth

Marcin

A ping command will always fail to Azure SQL from a public network as shown below:

C:\>ping <myserver>.database.windows.net

Pinging data.sn1-1.database.windows.net [65.55.74.144] with 32 bytes of data:
Request timed out.
Request timed out.
Request timed out.
Request timed out.
Ping statistics for 65.55.74.144:
Packets: Sent = 4, Received = 0, Lost = 4 (100% loss)

To block public access (including Telnet), you can set "Deny public network access" to "Yes" on the Firewall and virtual networks pane on the Azure portal. See detailed instructions here. In addition , remove any public IP addresses from the allowed list if they are not necessary.

Hi Julian,

No, you cannot block incoming telnet/ping to Azure SQL Database from public networks. The reason for this is the public IP for your Azure SQL logical Server serves multiple tenants.

When you telnet to the public IP on port 1433 you are actually connecting to a Azure SQL Gateway. It (the Gateway) does not have enough information at that point to determine whether or not the connection should be blocked.

Please see article below for more information:

Connectivity architecture

https://zcusa.951200.xyz/en-us/azure/azure-sql/database/connectivity-architecture?view=azuresql#connectivity-architecture

Please click Accept Answer and upvote if the above was helpful.

Thanks.

-TP