To allow network instances in different regions to communicate with each other, you must purchase a bandwidth plan and create cross-region connections. This topic describes how to create a cross-region connection.

Background information

Before you create a cross-region connection, take note of the following rules:
  • By default, a Basic Edition transit router supports 1 Kbit/s of bandwidth for cross-region connections. You do not need to create a cross-region connection if you want to test the network connectivity (IPv4) between regions.
  • An Enterprise Edition transit router provides 1 Kbit/s of bandwidth for network connectivity tests. You can use the provided bandwidth to create a cross-region connection and test the network connectivity between regions. You do not need to purchase a bandwidth plan.
  • If you want to enable data transmission across regions, both Basic Edition transit router and Enterprise Edition transit router require bandwidth plans that support cross-region network communication. For more information about how to purchase a bandwidth plan, see Work with a bandwidth plan.

    The sum of all bandwidth values in different regions cannot exceed the bandwidth value of the bandwidth plan. For example, a Cloud Enterprise Network (CEN) instance is associated with a 20 Mbit/s bandwidth plan that connects the Chinese mainland area to the North America area. You can set separate bandwidth values for cross-region connections between the US (Silicon Valley) region and regions in the Chinese mainland, such as China (Hangzhou), China (Shanghai), and China (Shenzhen). However, the sum of the bandwidth values cannot exceed 20 Mbit/s.

Use an Enterprise Edition transit router to create cross-region connections

  1. Log on to the CEN console.
  2. On the Instances page, find the CEN instance that you want to manage and click the instance ID.
  3. On the details page, you can use one of the following methods to go to the Connection with Peer Network Instance page and create a cross-region connection:
    • Navigate to the Basic Settings > Bandwidth Plans tab, and click Set Region Connection.
    • Navigate to the Basic Settings > Transit Router tab, find the transit router that you want to manage, and then click Create Connection in the Actions column.
      Note If no transit router is deployed in the region, choose the first method to create a cross-region connection. During the process, the system automatically creates a transit router instance.
  4. On the Connection with Peer Network Instance page, set the following parameters and click OK.
    Parameter Description
    Instance Type Select Cross-region.
    Region Select one of the regions to be connected.
    Transit Router Select the transit router in the selected region.

    If no transit router is found in the selected region, the system automatically creates a transit router.

    Connection Name Specify a name for the cross-region connection.

    The name must be 2 to 128 characters in length, and can contain digits, underscores (_), and hyphens (-). It must start with a letter.

    Bandwidth Allocation Mode transit router supports the following methods to allocate bandwidth:
    • Use Testing Bandwidth: By default, CEN provides 1 Kbit/s of bandwidth for you to test network connectivity (IPv4).

      If you want only to test the connectivity, you can select Use Testing Bandwidth.

    • Allocate from Bandwidth Plan: The bandwidth is allocated from a purchased bandwidth plan.

      If you want to create a cross-region connection, select Allocate from Bandwidth Plan.

    Peer Region Select the other region to be connected.
    Transit Router Select the transit router in the selected region.

    If no transit router is found in the selected region, the system automatically creates a transit router.

    Bandwidth Plan Select a bandwidth plan that is associated with the CEN instance.

    If you set Bandwidth Allocation Mode to Allocate from Bandwidth Plan, you must select a bandwidth plan.

    Bandwidth Specify a valid bandwidth value. Unit: Mbit/s.

    If you set Bandwidth Usage Mode to Allocate from Bandwidth Plan, you must specify a bandwidth value.

    Advanced Settings When you create a cross-region connection, the system automatically selects the following features in the advanced settings:
    • Associate with Default Route Table of Transit Router

      After this feature is enabled, the cross-region connection is automatically associated with the default route table of the transit router. The transit router uses the default route table to forward network traffic across regions.

    • Propagate System Routes to Default Route Table of Transit Router

      After this feature is enabled, the cross-region connection advertises system routes to the default route table of the transit router.

    • Automatically Advertise Routes to Peer Region

      After this feature is enabled, the routes of the transit router deployed in the current region are automatically advertised to the route table of the peer transit router. The routes are used for cross-region communication between network instances.

    Note
    • If you want to disable an advanced feature, clear the check box next to it. In this case, you can manually associate cross-region connections with route tables and configure route learning correlations. For more information, see Associated forwarding and Route learning.
    • When you create an associated forward correlation, you can associate a cross-region connection only with the default route table of a transit router.

Use a Basic Edition transit router to create cross-region connections

  1. Log on to the CEN console.
  2. On the Instances page, find the CEN instance that you want to manage and click the instance ID.
  3. On the details page, you can use one of the following methods to go to the Connection with Peer Network Instance page and create a cross-region connection:
    • Navigate to the Basic Settings > Bandwidth Plans tab, and click Set Region Connection.
    • Navigate to the Basic Settings > Transit Router tab, find the transit router that you want to manage, and then click Create Connection in the Actions column.
      Note If no transit router is deployed in the region, choose the first method to create a cross-region connection. During the process, the system automatically creates a transit router instance.
  4. On the Connection with Peer Network Instance page, set the following parameters and click OK.
    Parameter Description
    Instance Type Select Cross-region.
    Region Select one of the regions to be connected.
    Transit Router Select the transit router in the selected region.

    If no transit router is found in the selected region, the system automatically creates a transit router.

    Peer Region Select the other region to be connected.
    Transit Router Select the transit router in the selected region.

    If no transit router is found in the selected region, the system automatically creates a transit router.

    Bandwidth Plan Select a bandwidth plan that is associated with the CEN instance.
    Bandwidth Specify a valid bandwidth value. Unit: Mbit/s.

Modify bandwidth for cross-region connections

After you create a cross-region connection, you can modify the bandwidth value for the cross-region connection based on your business requirements.

  1. Log on to the CEN console.
  2. On the Instances page, find the CEN instance that you want to manage and click the instance ID.
  3. Navigate to the Basic Settings > Transit Router tab, find the transit router to which the cross-region connection belongs, and then click the ID of the transit router.
  4. On the details page of the transit router, click the Cross-region Connections tab.
  5. On the Cross-region Connections tab, find the cross-region connection that you want to manage and click Modify in the Bandwidth column.
  6. In the Set Region Connection dialog box, set the bandwidth value and click OK.
    The sum of all bandwidth values in different regions cannot exceed the bandwidth value of the bandwidth plan.

Delete a cross-region connection

Before you delete a cross-region connection from a Enterprise Edition transit router, make sure that the following requirements are met:
  1. Log on to the CEN console.
  2. On the Instances page, find the CEN instance that you want to manage and click the instance ID.
  3. Navigate to the Basic Settings > Transit Router tab, find the transit router to which the cross-region connection belongs, and then click the ID of the transit router.
  4. On the details page of the transit router, click the Cross-region Connections tab.
  5. On the Cross-region Connections tab, find the cross-region connection that you want to delete and click Delete in the Actions column.
  6. In the Delete Region Connection message, click OK.

References