Interconnect for Azure

Oracle Interconnect for Azure lets you create a cross-cloud connection between Oracle Cloud Infrastructure and Microsoft Azure in certain regions. This connection lets you set up cross-cloud workloads without the traffic between the clouds going over the internet. This topic describes how to set up virtual networking infrastructure resources to enable this kind of cross-cloud deployment.

For information about multicloud Oracle Database deployments that use Oracle Cloud Infrastructure and Microsoft Azure, see Oracle Database@Azure. This service hosts Oracle Exadata Databases in Azure data centers for the lowest possible latency.

Highlights

  • You can connect an Oracle Cloud Infrastructure (OCI) Virtual Cloud Network (VCN) with a Microsoft Azure virtual network (VNet) and run a cross-cloud workload. In the typical use case, you deploy an Oracle Database on OCI, and deploy an Oracle, .NET, or custom application in Microsoft Azure.
  • The two virtual networks must belong to the same company and not have overlapping CIDRs. Oracle Interconnect for Azure requires you to create an Azure ExpressRoute circuit and an OCI FastConnect virtual circuit.

Availability

Oracle Interconnect for Azure is only available in the OCI regions and ExpressRoute locations shown. For more information on Azure region locations and Azure ExpressRoute, see ExpressRoute peering locations and connectivity partners in the Azure documentation.

The following image shows regions with Oracle Interconnect for Azure, showing all OCI regions and noting regions with interconnect to both Azure and GCP. Participating Azure regions are also listed in the following tables.

Map showing which regions interconnect with Azure ExpressRoute.

Asia Pacific (APAC)

OCI location - key Azure ExpressRoute location Microsoft logo
Japan East (Tokyo) NRT Tokyo
Singapore (Singapore) - SIN Singapore
South Korea Central (Seoul) - ICN Seoul

Europe, Middle East, Africa (EMEA)

OCI location Azure ExpressRoute location Microsoft logo
Germany Central (Frankfurt) - FRA Frankfurt and Frankfurt2
Netherlands Northwest (Amsterdam) - AMS Amersterdam2
UK South (London) - LHR London
South Africa Central (Johannesburg) - JNB Johannesburg

Latin America (LATAM)

OCI location Azure ExpressRoute location Microsoft logo
Brazil Southeast (Vinhedo) - VCP Campinas

North America (NA)

OCI location Azure ExpressRoute location Microsoft logo
Canada Southeast (Toronto) - YYZ Toronto and Toronto2
US East (Ashburn) - IAD Washington DC and Washington DC2
US West (Phoenix) - PHX Phoenix
US West (San Jose) - SJC Silicon Valley

Overview of Supported Traffic

Here are more details about the supported types of traffic.

VCN-to-VNet Connection: Extension from One Cloud to Another

You can connect a VCN and VNet so that traffic that uses private IP addresses goes over the cross-cloud connection.

For example, the following diagram shows a VCN connected to a VNet. Resources in the VNet are running a .NET application that access an Oracle database that runs on Database service resources in the VCN. The traffic between the application and database uses a logical circuit that runs on the cross-cloud connection between Azure and Oracle Cloud Infrastructure.

This diagram shows the connection between an Azure VNet and Oracle VCN.

To enable the connection between the VCN and VNet, you set up both an Oracle Cloud Infrastructure FastConnect virtual circuit and an Azure ExpressRoute circuit. The connection has built-in redundancy, which means you need to set up only a single FastConnect virtual circuit and a single ExpressRoute circuit. The bandwidth for the connection is the bandwidth value you select for the ExpressRoute circuit.

For instructions, see Setting Up a Connection.

Peered VCNs

The connection lets traffic flow from the VNet through the connected VCN to a peered VCN in the same Oracle Cloud Infrastructure region, or a different region.

Types of Traffic Not Supported by the Connection

This cross-cloud connection doesn't enable traffic between the on-premises network through the VCN to the VNet, or from the on-premises network through the VNet to the VCN.

Important Implications of Connecting Clouds

This section summarizes some access control, security, and performance implications of Oracle Interconnect for Azure. In general, you can control access and traffic by using IAM policies, route tables in the VCN, and security rules in the VCN.

The sections that follow discuss implications from the perspective of the VCN. Similar implications affect the VNet. As with the VCN, you can use Azure resources such as route tables and network security groups to secure the VNet.

Controlling the Establishment of a Connection

With Oracle Cloud Infrastructure IAM policies, you can control:

Controlling Traffic Flow Over the Connection

Even if a connection has been established between the VCN and VNet, you can control the packet flow over the connection with route tables in the VCN. For example, you can restrict traffic to only specific subnets in the VNet.

Without deleting the connection, you can stop traffic flow to the VNet by removing route rules that direct traffic from the VCN to the VNet. You can also effectively stop the traffic by removing any security rules that enable ingress or egress traffic with the VNet. This doesn't stop traffic flowing over the connection, but stops it at the VNIC level.

Controlling the Specific Types of Traffic Allowed

Ensure that all outbound and inbound traffic with the VNet is intended or expected and as defined. Implement Azure network security group and Oracle security rules that explicitly state the types of traffic one cloud can send to the other and accept from the other.

Important

Oracle Cloud Infrastructure instances running Linux or Windows platform images also have firewall rules that control access to the instance. When troubleshooting access to an instance, ensure that the following items are set correctly: the network security groups that the instance is in, the security lists associated with the instance's subnet, and the instance's firewall rules.

If an instance is running Oracle Autonomous Linux 8.x, Oracle Autonomous Linux 7, Oracle Linux 8, Oracle Linux 7, or Oracle Linux Cloud Developer 8, you need to use firewalld to interact with the iptables rules. For reference, here are commands for opening a port (1521 in this example):

sudo firewall-cmd --zone=public --permanent --add-port=1521/tcp
								
sudo firewall-cmd --reload

For instances with an iSCSI boot volume, the preceding --reload command can cause problems. For details and a workaround, see Instances experience system hang after running firewall-cmd --reload.

In addition to security rules and firewalls, evaluate other OS-based configuration on the instances in the VCN. There could be default configurations that don't apply to the VCN's CIDR, but inadvertently apply to the VNet's CIDR.

Using Default Security List Rules with the VCN

If the VCN's subnets use the default security list with the default rules, two rules in that list allow ingress traffic from anywhere (0.0.0.0/0, and thus the VNet):

  • Stateful ingress rule that allows TCP port 22 (SSH) traffic from 0.0.0.0/0 and any source port
  • Stateful ingress rule that allows ICMP type 3, code 4 traffic from 0.0.0.0/0 and any source port

Evaluate these rules and whether you want to keep or update them. As stated earlier, ensure that all allowed inbound or outbound traffic is intended or expected and as-defined.

Preparing for Performance Impact and Security Risks

In general, prepare the VCN for the ways it could be affected by the VNet. For example, the load on the VCN or its instances could increase. Or the VCN could experience a malicious attack directly from or by way of the VNet.

Regarding performance: If the VCN is providing a service to the VNet, be prepared to scale up the service to accommodate the demands of the VNet. This might mean being prepared to create more instances as necessary. Or if you're concerned about high levels of network traffic coming to the VCN, consider using stateless security rules to limit the level of connection tracking the VCN must perform. Stateless security rules can also help slow the impact of a denial-of-service (DoS) attack.

Regarding security risks: If the VNet is connected to the internet, the VCN can be exposed to bounce attacks. A bounce attack involves a malicious host on the internet sending traffic to the VCN that seems to be coming from the VNet. To guard against this, as mentioned earlier, use security rules to carefully limit the inbound traffic from the VNet to expected and as-defined traffic.

Setting Up a Connection

This section describes how to set up the logical connection between a VCN and VNet (for background, see Overview of Supported Traffic).

Prerequisites: Resources You Need

You must already have:

  • An Azure VNet with subnets and virtual network gateway
  • An Oracle Cloud Infrastructure VCN with subnets and an attached Dynamic Routing Gateway (DRG). Remember to attach the DRG to the VCN after you create it. If you already have Site-to-Site VPN or FastConnect between the on-premises network and VCN, then the VCN already has an attached DRG. You use that same DRG here when setting up the connection to Azure.

As a reminder, here is a table that lists the comparable networking components involved in each side of the connection.

Component Azure Oracle Cloud Infrastructure
Virtual network VNet VCN
Virtual circuit ExpressRoute circuit FastConnect private virtual circuit
Gateway virtual network gateway Dynamic Routing Gateway (DRG)
Routing route tables route tables
Security rules network security groups (NSGs) network security groups (NSGs), security lists

Prerequisites: BGP Information You Need

The connection between the VCN and VNet uses BGP dynamic routing. When you set up the Oracle virtual circuit, you provide the BGP IP addresses used for the two redundant BGP sessions between Oracle and Azure:

  • A primary pair of BGP addresses (one IP address for the Oracle side, one IP address for the Azure side)
  • A separate, secondary pair of BGP addresses (one IP address for the Oracle side, one IP address for the Azure side)

For each pair, you must provide a separate block of addresses with a subnet mask from /28 to /31.

The second and third addresses in each address block are used for the BGP IP address pair:

  • The second address in the block is for the Oracle side of the BGP session
  • The third address in the block is for the Azure side of the BGP session

The first and last addresses in the block are used for other internal purposes.

For example, if the CIDR is 10.0.0.20/30, then the addresses in the block are:

  • 10.0.0.20
  • 10.0.0.21: Use this for the Oracle side (in the Oracle Console, enter the address as 10.0.0.21/30)
  • 10.0.0.22: Use this for the Azure side (in the Oracle Console, enter the address as 10.0.0.22/30, and notice that this address is referred to as the "Customer" side in the Console)
  • 10.0.0.23

Remember that you must also provide a second block with the same size for the secondary BGP addresses. For example: 10.0.0.24/30. In this case, 10.0.0.25 is for the Oracle side, and 10.0.0.26 is for the Azure side. In the  Oracle Console, you must enter these as 10.0.0.25/30 and 10.0.0.26/30.

Prerequisites: Required IAM Policy

You probably have the necessary Azure Active Directory access and Oracle Cloud Infrastructure IAM access to create and work with the relevant Azure and Oracle networking resources. For IAM: If your user account is in the Administrators group, you have the required authority. Otherwise, this policy covers all the Networking resources:

Allow group NetworkAdmins to manage virtual-network-family in tenancy

To only create and manage a virtual circuit, you must have a policy such as this:

Allow group VirtualCircuitAdmins to manage drgs in tenancy

Allow group VirtualCircuitAdmins to manage virtual-circuits in tenancy

For more information, see IAM Policies for Networking.

Overall Process

The following diagram shows the overall process of connecting the VCN and VNet.

This swimlane diagram shows the steps for connecting an Oracle VCN and Azure VNet

Managing Oracle Interconnect for Azure