There are multiple steps involved in configuring Azure ExpressRoute, and each step necessitates collaboration with a connectivity or network service provider (NSP) who will aid in setting up the physical connections. A high-level summary of the configuration procedure is provided below:
Resource and Subscription Group: Ensure that you have created a resource group and an Azure subscription in your Azure portal. If not, make some.
Choose a provider for ExpressRoute: Pick an ISP or ExpressRoute provider that provides services for ExpressRoute in your area. You can pick from a list of ExpressRoute partners provided by Microsoft.
Create a Virtual Network Gateway: Create a Virtual Network Gateway in your Azure virtual network through the Azure portal. The gateway serves as your ExpressRoute connection's entry point.
Configure Peering: Configure your virtual network gateway's peering settings. The peering arrangement with your ExpressRoute circuit must be specified. Peering is divided into two categories: Microsoft and Private. While Microsoft peering connects to various Microsoft services, private peering links your on-premises network to your Azure virtual network.
Create Route Tables: Plan out your Azure virtual network's route tables. The traffic between your on-premises network and Azure resources is routed using these route tables.
Set Up BGP (Border Gateway Protocol): Configure the BGP settings on your on-premises router and the router that your ExpressRoute provider provides if you are utilizing BGP for dynamic routing. In order to advertise routes between your on-premises network and Azure dynamically, BGP is helpful.
Cross-Connection Configuration: To achieve high availability and failover, configure cross-connection between the two ExpressRoute circuits if you have redundant connections.
Testing and Validation: Carefully test and validate connections and routing before deploying your ExpressRoute connection. Verify that traffic behaves as expected and that failover systems function as planned.
Monitoring and Management: Once the link is operational, make sure to maintain and monitor it frequently. Track the functionality and health of your ExpressRoute circuit with Azure Network Watcher and other Azure monitoring tools.
Security Considerations: To safeguard your network traffic using ExpressRoute, put the required security mechanisms in place, such as Network Security Groups (NSGs) and Azure Firewall.
Documentation and Maintenance: Keep thorough records of your ExpressRoute settings, including IP address allocations, routing configurations, and your ExpressRoute provider's contact information. As your network changes, update this material frequently.
Working closely with your ExpressRoute provider or NSP is essential throughout the configuration process as they will have unique needs and guidelines for establishing the physical connections and configuring the routers. To guarantee a seamless and secure deployment, you should also adhere to Azure's documentation and instructions for ExpressRoute configuration.