Firewall rules in Azure Database for PostgreSQL - Single Server
Azure Database for PostgreSQL server firewall prevents all access to your database server until you specify which computers have permission. The firewall grants access to the server based on the originating IP address of each request. To configure your firewall, you create firewall rules that specify ranges of acceptable IP addresses. You can create firewall rules at the server level.
Firewall rules: These rules enable clients to access your entire Azure Database for PostgreSQL Server, that is, all the databases within the same logical server. Server-level firewall rules can be configured by using the Azure portal or using Azure CLI commands. To create server-level firewall rules, you must be the subscription owner or a subscription contributor.
All database access to your Azure Database for PostgreSQL server is blocked by the firewall by default. To begin using your server from another computer, you need to specify one or more server-level firewall rules to enable access to your server. Use the firewall rules to specify which IP address ranges from the Internet to allow. Access to the Azure portal website itself is not impacted by the firewall rules. Connection attempts from the Internet and Azure must first pass through the firewall before they can reach your PostgreSQL Database, as shown in the following diagram:
Connecting from the Internet
Server-level firewall rules apply to all databases on the same Azure Database for PostgreSQL server. If the IP address of the request is within one of the ranges specified in the server-level firewall rules, the connection is granted. If the IP address of the request is not within the ranges specified in any of the server-level firewall rules, the connection request fails. For example, if your application connects with JDBC driver for PostgreSQL, you may encounter this error attempting to connect when the firewall is blocking the connection.
java.util.concurrent.ExecutionException: java.lang.RuntimeException: org.postgresql.util.PSQLException: FATAL: no pg_hba.conf entry for host "126.96.36.1990", user "adminuser", database "postgresql", SSL
Connecting from Azure
To allow applications from Azure to connect to your Azure Database for PostgreSQL server, Azure connections must be enabled. For example, to host an Azure Web Apps application, or an application that runs in an Azure VM, or to connect from an Azure Data Factory data management gateway. The resources do not need to be in the same Virtual Network (VNet) or Resource Group for the firewall rule to enable those connections. When an application from Azure attempts to connect to your database server, the firewall verifies that Azure connections are allowed. There are a couple of methods to enable these types of connections. A firewall setting with starting and ending address equal to 0.0.0.0 indicates these connections are allowed. Alternatively, you can set the Allow access to Azure services option to ON in the portal from the Connection security pane and hit save. If the connection attempt is not allowed, the request does not reach the Azure Database for PostgreSQL server.
This option configures the firewall to allow all connections from Azure including connections from the subscriptions of other customers. When selecting this option, make sure your login and user permissions limit access to only authorized users.
Programmatically managing firewall rules
In addition to the Azure portal, firewall rules can be managed programmatically using Azure CLI. See also Create and manage Azure Database for PostgreSQL firewall rules using Azure CLI
Troubleshooting the database server firewall
Consider the following points when access to the Microsoft Azure Database for PostgreSQL Server service does not behave as you expect:
Changes to the allow list have not taken effect yet: There may be as much as a five-minute delay for changes to the Azure Database for PostgreSQL Server firewall configuration to take effect.
The login is not authorized or an incorrect password was used: If a login does not have permissions on the Azure Database for PostgreSQL server or the password used is incorrect, the connection to the Azure Database for PostgreSQL server is denied. Creating a firewall setting only provides clients with an opportunity to attempt connecting to your server; each client must still provide the necessary security credentials.
For example, using a JDBC client, the following error may appear.
java.util.concurrent.ExecutionException: java.lang.RuntimeException: org.postgresql.util.PSQLException: FATAL: password authentication failed for user "yourusername"
Dynamic IP address: If you have an Internet connection with dynamic IP addressing and you are having trouble getting through the firewall, you could try one of the following solutions:
Ask your Internet Service Provider (ISP) for the IP address range assigned to your client computers that access the Azure Database for PostgreSQL Server, and then add the IP address range as a firewall rule.
Get static IP addressing instead for your client computers, and then add the static IP address as a firewall rule.
For articles on creating server-level and database-level firewall rules, see: