Fast failover for VBRs attached to an ECR - Express Connect

When an Express Connect circuit fails, it can take 10 seconds or more for the system to detect the failure and complete the route switchover, depending on the number of routes. Alibaba Cloud Express Connect is optimized to reduce this failover time. When you attach multiple virtual border routers (VBRs) to an Express Connect Router (ECR), you can enable fast failover for two or more of the VBRs. When Bidirectional Forwarding Detection (BFD) detects a fault, traffic automatically switches from the faulty VBR to a backup VBR. This process completes failover in seconds and ensures service continuity.

Usage notes

Each VBR can join only one failover group. A failover group can contain up to 8 VBRs. You can create a maximum of 64 failover groups.
All VBRs in a failover group must be in the same region but connect to different physical access points.
If a VBR already has a failover group configured, you must first disable that configuration before assigning the VBR to a new failover group on the ECR.
Only VBRs with BFD enabled can join a failover group.
You can enable a failover group only when the status of all VBRs in the group is Normal.

Prerequisites

You have created multiple virtual border routers at different access points within the same region. Each VBR is connected to your on-premises data center through a separate Express Connect circuit. For more information, see Add and manage route entries.
Before you add multiple VBRs to the same failover group, make sure that the VBRs meet the following requirements:
- The Express Connect circuit ports connected to the VBRs must support the multiple failover groups feature.
- BFD is enabled for each VBR, and all VBRs are attached to the same ECR.

Procedure

Log on to the Express Connect console.
In the left-side navigation pane, click Express Connect Router (ECR), and then click the target ECR instance.

In the Failover Group ID column of the target VBR instance, click the edit icon. Select a Failover Group ID and click OK.

Failover group status	Description
Enabled	VBRs with the same Failover Group ID form a single failover group.
Not supported	The connected Express Connect circuit port does not support multiple failover groups, so you cannot configure a failover group for the VBR.
Disabled	To remove a VBR from a failover group, click the edit icon in the Failover Group ID column, select Disabled, and then click OK.

Note

You can also select multiple VBRs and click Batch Modify at the bottom of the VBR tab to configure their Failover Group IDs.