Process of Using Enterprise Router to Migrate the Network Set Up Through Direct Connect

Step 1: Create an Enterprise Router and a VPC Attachment

1. Create an enterprise router ER-X in the same region as the service VPC.
2. Create a VPC attachment er-attach-VPC-X to attach the service VPC to the enterprise router.
3. Verify that routes are automatically added to the enterprise router route table.
4. In the VPC route table, add a route destined for the large CIDR block with the enterprise router as the next hop.

Step 2: Attach Global DC Gateway DGW-B01 to the Enterprise Router

1. Create a global DC gateway DGW-B01.

   DGW-B01 is used to replace VGW-A after the migration.

2. Delete virtual interface VIF-A01 associated with virtual gateway VGW-A.

   Before deleting virtual interface VIF-A01, delete the configuration on the on-premises network device to ensure that traffic does not pass through this virtual interface.

3. Create virtual interface VIF-B01 for global DC gateway DGW-B01 and attach the global DC gateway to the enterprise router.

   VIF-B01 is used to replace VIF-A01 after the migration.

4. (Optional) Configure the on-premises network device to enable the on-premises data center to access cloud resources through the new virtual interface VIF-B01 or a specified virtual interface.

Step 3: Verify Communications Between the VPC and On-Premises Data Center Through the Enterprise Router

1. In the VPC route table, add a route destined for any on-premises server to verify communications between the VPC and on-premises data center.
2. Create an ECS in the VPC subnet that needs to communicate with the on-premises data center, log in to the ECS, and run the ping command.
3. Delete the route and ECS used for verifying communications.

Step 4: Attach Global DC Gateway DGW-B02 to the Enterprise Router

1. Create a global DC gateway DGW-B02.

   DGW-B02 is used to replace VGW-A after the migration.

2. Delete virtual interface VIF-A02 associated with virtual gateway VGW-A.

   Before deleting virtual interface VIF-A02, delete the configuration on the on-premises network device to ensure that traffic does not pass through this virtual interface.

3. Create virtual interface VIF-B02 for global DC gateway DGW-B02 and attach the global DC gateway to the enterprise router.

   VIF-B02 is used to replace VIF-A02 after the migration.

4. (Optional) Configure the on-premises network device to enable the on-premises data center to access cloud resources through the new virtual interface VIF-B02 or a specified virtual interface.

Step 5: Configure the Working Mode of the Connections

Configure a route policy to make the two connections to work in load balancing or active/standby mode based on site requirements.

Step 6: Delete the Virtual Gateway

When the on-premises data center can access the VPC through the enterprise router, delete virtual gateway VGW-A.