An Enterprise Edition transit router provides advanced features, such as custom route tables, custom route entries, traffic policies, and flow logs, for an enhanced network connectivity experience. This topic describes how to upgrade a Basic Edition transit router to an Enterprise Edition transit router.
Background information
During the upgrade, the system converts the dynamic route entries learned from Cloud Enterprise Network (CEN) in a Virtual Private Cloud (VPC) instance into custom route entries with the next hop pointing to an Enterprise Edition transit router. The conversion does not affect your services.
After the upgrade, the Enterprise Edition transit router does not automatically propagate routes to the VPC-connected instance. To enable automatic route propagation, you must enable route synchronization for the VPC-connected instance. For more information, see Route synchronization.
You cannot upgrade Basic Edition transit routers in Cloud Connect Network (CCN) regions. For a list of regions that support the upgrade, see Supported regions and zones for Enterprise Edition transit routers.
Step 1: Schedule the upgrade
Before you upgrade a Basic Edition transit router, you must request forwarding resources. It can take up to 72 hours for these resources to become active. Therefore, you must schedule the upgrade at least 72 hours in advance. For an emergency upgrade, contact your account manager.
Network interruptions may occur during the upgrade. Migrate your service traffic, notify end users about the network change, and perform the upgrade during off-peak hours.
The upgrade takes 10 to 20 minutes. To ensure that the upgrade is successful, reserve a 1-hour window for the operation.
Log on to the CEN console.
On the Instances page, click the ID of the CEN instance that you want to manage.
On the details page of the CEN instance, you can navigate to the upgrade page using one of the following methods:
On the tab, locate the target Basic Edition transit router instance and click Upgrade in the Version column.
On the tab, find the target Basic Edition transit router instance and click its ID. On the details page of the transit router, click the Basic Settings tab, and then click Upgrade next to Version.
In the Upgrade Transit Routers to Enterprise Edition dialog box, review the features and billing information for the Enterprise Edition transit router, and then click Upgrade.
On the Schedule Upgrade page in the wizard, select the zones for the Enterprise Edition transit router, and then click Schedule Upgrade.
Enterprise Edition transit routers support one or more zones across different regions. During the upgrade, the Enterprise Edition transit router creates an elastic network interface (ENI) in a vSwitch in each selected zone. The ENI is used to forward traffic between the VPC-connected instance and the Enterprise Edition transit router.
For regions where the Enterprise Edition transit router supports multiple zones, such as China (Hangzhou), select at least two zones to ensure high availability. For information about the zones supported by Enterprise Edition transit routers, see the Background information section in this topic.
NoteIn regions where the Enterprise Edition transit router supports multiple zones, select all available zones. This helps reduce traffic detours, lower transmission delays, and improve the performance of traffic between the VPC and the Enterprise Edition transit router. For more information about how traffic is transmitted between a VPC and an Enterprise Edition transit router, see VPC connection routing principles.
After you schedule the upgrade, Alibaba Cloud requests forwarding resources and approves your request within 72 hours. Once the request is approved, the status on the Schedule Upgrade page changes to Migration Completed. A status of Migration Completed indicates that the forwarding resources are ready. You must then complete the preparations and start the upgrade as described in the following sections.
Step 2: Preparations
Before you start the upgrade, complete the following preparations to ensure that the upgrade is successful.
If the Basic Edition transit router is connected to VPC-connected instances, prepare vSwitch resources for each VPC-connected instance.
You must prepare vSwitch resources to ensure that the Enterprise Edition transit router can successfully connect to VPC-connected instances. Ensure that each VPC-connected instance under the Basic Edition transit router has a vSwitch in each zone that you specified for the Enterprise Edition transit router. The Enterprise Edition transit router creates an ENI on the vSwitch in each zone. The ENI is used to forward traffic between the VPC-connected instance and the Enterprise Edition transit router. The ENI uses one IP address from the vSwitch. Make sure that the vSwitch has sufficient IP addresses. For more information, see Create a vSwitch.
For example, you want to upgrade a Basic Edition transit router in the China (Hangzhou) region. The Basic Edition transit router is connected to two VPC-connected instances, VPC1 and VPC2. If you specified Zone H and Zone I as the zones for the transit router in Step 1, you must ensure that VPC1 has a vSwitch in Zone H and Zone I, and VPC2 has a vSwitch in Zone H and Zone I.
NoteIf vSwitches already exist in the zones supported by the Enterprise Edition transit router, you cannot use them. Create a separate vSwitch in each supported zone for the Enterprise Edition transit router to connect to the VPC-connected instances. When you create the vSwitches, follow these principles:
When you create a vSwitch, use the smallest possible CIDR block to save IP address resources.
The mask length of the vSwitch CIDR block cannot be greater than 28. For example, you can set the CIDR block of the vSwitch to 192.168.10.0/28.
If you use network ACLs in your network, attach the new vSwitches to the same network ACL. The inbound and outbound rules of the network ACL must allow all traffic. You can attach vSwitches that carry service traffic to other network ACLs for traffic shaping.
Attach the new vSwitches to the same VPC route table.
If the Basic Edition transit router is connected to a virtual border router (VBR) instance, you do not need to perform any operations on the VBR instance.
Back up route entries.
Before the upgrade, back up all route entries of the current CEN instance. After the upgrade, you can compare the route entries with the backup to ensure that they are consistent.
Log on to the Cloud Enterprise Network console.
On the Instances page, find the target CEN instance and click its ID.
On the tab, find the Basic Edition transit router instance and click its ID.
On the details page of the transit router instance, click the Route Table tab.
On the Route Table tab, click the
icon to download the route entries in the current region. Save the route entries to your local computer.Repeat the preceding steps to download and save the route entries in all regions of the CEN instance.
If required, prepare test resources. After the upgrade, use these resources to test network connectivity.
Step 3: Start the upgrade
After your scheduled request is approved and you have completed the preparations, you can start the upgrade.
Log on to the Cloud Enterprise Network console.
On the Instances page, click the ID of the CEN instance that you want to manage.
On the details page of the CEN instance, you can navigate to the upgrade page using one of the following methods:
On the tab, locate the target Basic Edition transit router instance and click Upgrade in the Version column.
On the tab, find the target Basic Edition transit router instance and click its ID. On the details page of the transit router, click the Basic Settings tab, and then click Upgrade next to Version.
In the Upgrade Transit Routers to Enterprise Edition dialog box, click Upgrade.
On the Schedule Upgrade page of the wizard, click Next.
On the Specify Virtual Switch page of the wizard, configure the parameters as described in the following table, and click Next.
Configuration item
Description
Request Transit Router Zone Resources
The system automatically reads the zone information that you selected on the Schedule Upgrade page.
Delete Default Cloud Service
Select Delete Default Cloud Service.
Notes on Creating Service Linked Roles
When you upgrade a Basic Edition transit router, the system automatically creates a service-linked role named AliyunServiceRoleForCEN. This role allows the Enterprise Edition transit router to create ENIs on the vSwitches of the destination VPC-connected instance. The ENIs serve as interfaces for traffic between the VPC-connected instance and the Enterprise Edition transit router. For more information about service-linked roles, see AliyunServiceRoleForCEN.
Select the vSwitch to which the VPC is connected.
Select a vSwitch for the VPC connection.
The Enterprise Edition transit router will create an ENI on the vSwitch that you specify.
If the vSwitch that you select is attached to a network ACL, make sure that the inbound and outbound rules of the network ACL allow all traffic. Otherwise, the network ACL may affect traffic between the Enterprise Edition transit router and the VPC-connected instance.
In the Configure VPC Route step, select Automatically Switch to Static Routes and then click Next.
On the Confirm Configuration and Price page of the wizard, confirm the network instance information, read the billing description and select the checkbox to agree, and then click Next.
In the All Upgrade Deployments Completed, Upgrade Will Begin Soon dialog box, specify a time for the upgrade or select Upgrade Now, and then click Confirm.
If you specify a time for the upgrade, the system automatically starts the upgrade at the specified time. Do not perform other operations on the Basic Edition transit router until the upgrade is complete.
If you select Upgrade Now, the upgrade starts automatically. No further action is required.
Step 4: Verification and testing
After the upgrade is complete, compare the route entries and test the network connectivity of your services to verify that the upgrade is successful.
Compare route entries.
You can view or download the route entries after the upgrade and compare them with the route entries that you backed up to ensure that they are consistent.
Log on to the Cloud Enterprise Network console.
On the Instances page, find the CEN instance to manage and click its ID.
On the tab, find the target Enterprise Edition transit router instance and click its ID.
On the transit router instance details page, click the Route Table tab.
On the Route Entry tab, you can view the route entries in the current region.
If you have many route entries, you can click the
icon to download the route entries in the current region.
Test the network connectivity to ensure that all services run as expected.
FAQ
After a Basic Edition transit router is upgraded to an Enterprise Edition transit router, can it be downgraded to a Basic Edition transit router?
No, you cannot.
The upgrade from a Basic Edition transit router to an Enterprise Edition transit router is irreversible.