File Storage NAS:Use CEN to mount a NAS file system across accounts and regions

Feature description

CEN is a highly available network built on the global private network of Alibaba Cloud. CEN uses transit routers to establish cross-region connections between VPCs. This enables VPCs to communicate with data centers and establish flexible, reliable, and enterprise-class networks in the cloud.

Transit routers are available in two editions: Basic Edition and Enterprise Edition. Enterprise Edition is an upgraded version of Basic Edition and supports all features of Basic Edition. In addition, Enterprise Edition supports custom routing policies. For more information, see How transit routers work. For more information about the regions supported by each edition of transit routers, see Transit router editions.

Step 1: Grant permissions to the accounts

Before you can connect VPC2 that belongs to Account B to the transit router that belongs to Account A, you must grant the required permissions to Account A. Otherwise, the transit router that belongs to Account A cannot connect to VPC2.

1. Log on to the VPC console with Account B.

2. In the top navigation bar, select the region where VPC2 is deployed. In this example, China (Guangzhou) is selected.

3. On the VPCs page, find and click the ID of VPC2.

4. Click the Cross-account authorization tab. On the tab, click Authorize Cross Account Attach CEN.

5. In the Attach to CEN dialog box, configure the parameters and click OK. The following table describes the parameters.

   Parameter	Description
   Peer Account UID	Enter the ID of the Alibaba Cloud account that owns the transit router. In this example, enter the UID of Account A.
   Peer CEN Instance ID	Enter the ID of the CEN instance to which the transit router belongs. In this example, enter the ID of the CEN instance that belongs to Account A.
   Payer	Select the account that pays the fees. CEN Instance Owner Pays Bills: The owner of the transit router pays the connection fee and data transfer fee. This is the default value. VPC Owner: The owner of the VPC pays the connection fee and data transfer fee. In this example, use the default value. Note If you use Basic Edition transit routers to connect VPCs, connections and data transfer are free of charge.

Step 2: Connect the VPCs to the transit router

After Account A is granted the required permissions, you must connect VPC1, VPC2, and VPC3 to the transit router that belongs to Account A. This enables network communication between the VPCs.

1. Log on to the CEN console with Account A.

2. On the Instances page, click the ID of the CEN instance that you want to manage.

3. On the Basic Settings tab, click in the VPC section.
   

4. On the Connection with Peer Network Instance page, configure the following parameters and click OK:

   • Network Type: Select the type of network instance that you want to attach.

   • Region: Select the region where the network instance is deployed.

   • Transit Router: The transit router in the selected region is automatically displayed.

   • Resource Owner ID: Select the Alibaba Cloud account to which the network instance belongs.

   • Network Instance: Select the ID of the network instance that you want to attach.

   The system connects VPC1, VPC2, and VPC3 to the transit router that belongs to Account A based on the preceding settings. The following table lists the settings of each VPC.

   Parameter	VPC1	VPC2	VPC3
   Network Type	VPC	VPC	VPC
   Region	China (Guangzhou)	China (Guangzhou)	China (Ulanqab)
   Resource Owner ID	Current Account	Different Account If you select Different Account, you must specify the ID of Account B.	Current Account
   Network Instance	VPC1	VPC2	VPC3

   After you complete the preceding steps, VPC1, VPC2, and VPC3 automatically learn routes from each other. VPC1 and VPC2 can communicate with each other. Inter-region connections are established between VPC1 and VPC3, and between VPC2 and VPC3. By default, CEN provides 1 Kbit/s of bandwidth for connectivity testing (IPv4 addresses). The bandwidth is used only for testing and does not support service-level inter-region connections. For example, you can create an ECS in each VPC and run the ping command in ECS instances to test connectivity.

Step 3: Purchase a bandwidth plan

To establish connections between VPC1 and VPC3, and between VPC2 and VPC3, you must purchase a bandwidth plan that provides bandwidth for inter-region connections.

1. Log on to the CEN console with Account A.

2. On the Instances page, click the ID of the CEN instance that you want to manage.

3. On the details page of the CEN instance, choose Basic Settings > Bandwidth Plans, and click Purchase Bandwidth Plan (Subscription).

4. On the buy page, configure the parameters, click Buy Now, and then complete the payment. The following table describes the parameters.

   Parameter	Description
   CEN ID	Select the CEN instance for which you want to purchase a bandwidth plan. After you complete the payment, the bandwidth plan is automatically associated with the CEN instance. In this example, select the CEN instance that belongs to Account A.
   Area A	Select one of the areas where you want to enable inter-region communication. In this example, select Mainland China. Note You cannot change the areas after the bandwidth plan is purchased. For more information about the regions and areas that support bandwidth plans, see Work with a bandwidth plan.
   Area B	Select one of the areas where you want to enable inter-region communication. In this example, select Mainland China.
   Billing Method	The billing method of the bandwidth plan. Default value: Pay-By-Bandwidth. For more information, see Billing rules.
   Bandwidth	Select a bandwidth value based on your business requirements. Unit: Mbit/s.
   Bandwidth Package Name	Enter a name for the bandwidth plan.
   Order time	Select a subscription duration for the bandwidth plan. You can select Auto-renewal to enable auto-renewal for the bandwidth plan.
   Resource Group	Select the resource group to which the bandwidth plan belongs.

Step 4: Create an inter-region connection

1. Log on to the CEN console with Account A.

2. On the Instances page, click the ID of the CEN instance that you want to manage.

3. Go to the Basic Settings > Bandwidth Plans tab and click Assign Bandwidth.

4. On the Connection with Peer Network Instance page, configure the parameters and click OK. The following table describes the parameters.

   Parameter	Description
   Instance Type	In this example, select Inter-region Connection.
   Region	Select one of the regions to be connected. In this example, select China (Guangzhou).
   Transit Router	The ID of the transit router in the selected region is automatically displayed.
   Peer Region	Select the other region to be connected. In this example, select China (Ulanqab).
   Transit Router	The ID of the transit router in the selected region is automatically displayed.
   Bandwidth Plan	Select a bandwidth plan that is associated with the CEN instance.
   Bandwidth	Specify a bandwidth value for inter-region connections. Unit: Mbit/s.

Step 5: Test network connectivity

After you complete the preceding steps, VPC1, VPC2, and VPC3 are connected to each other. This section describes how to test the network connectivity between the VPCs.

1. Test the network connectivity between VPC1 and VPC2.

   1. Log on to an ECS instance in VPC 1. For more information, see Connection method overview.

   2. On the ECS instance, run the ping command to test whether you can access the ECS instance in VPC2.

      ping

      <The IP address of the ECS instance in VPC2>

      The following echo reply packet indicates that VPC1 can communicate with VPC2.

      

2. Test the network connectivity between VPC1 and VPC3.

   1. Log on to an ECS instance in VPC 3.

   2. On the ECS instance, run the ping command to test whether you can access an ECS instance in VPC1.

      # Send a ping packet that is 2,000 bytes in length to test whether VPC1 and VPC3 can communicate with each other across regions. 
      ping <The IP address of the ECS instance in VPC1>  -s 2000

      The following echo reply packet indicates that VPC1 can communicate with VPC3.

3. Test the network connectivity between VPC2 and VPC3.

   1. Log on to an ECS instance in VPC 3.

   2. On the ECS instance, run the ping command to test whether you can access an ECS instance in VPC2.

      # Send a ping packet that is 2,000 bytes in length to test whether VPC2 and VPC3 can communicate with each other across regions. 
      ping <The IP address of the ECS instance in VPC2>   -s 2000

      The following echo reply packet indicates that VPC2 can communicate with VPC3.

Step 6: Mount the file system

After you complete the preceding configurations, mount the file system on an ECS instance across accounts and regions.

References

• You can mount a NAS file system across VPCs by using PrivateLink or CEN. For more information, see Use PrivateLink to mount a NAS file system across VPCs in the same region or Use CEN to mount a NAS file system across VPCs in the same region.

• You can mount a NAS file system in an on-premises data center. For more information, see Access file systems in on-premises data centers.

• You can migrate data from an on-premises storage system or Object Storage Service (OSS) bucket to a NAS file system. For more information, see Data migration.