You can create a custom route table for a virtual private cloud (VPC) and add subnet
routes to the custom route table. Then, you can associate the custom route table with
a vSwitch to manage the traffic of the vSwitch. This facilitates network management.
Prerequisites
A VPC is created. For more information, see
Create a VPC.
Background
Before you add subnet routes to a custom route table, take note of the following limits:
- Each VPC can contain at most 10 route tables including the system route table.
- Each vSwitch can be associated with only one system route table or one custom route
table.
- Custom route tables do not support active or standby routes, or load-balancing routes.
Step 1: Create a custom route table
- Log on to the VPC console.
- In the left-side navigation pane, click Route Tables.
- Select the region where you want to create a custom route table.
- On the Route Tables page, click Create Route Table.
- In the Create Route Table dialog box, set the following parameters and click OK.
Parameter |
Description |
Resource Group |
Select the resource group to which the route table belongs. |
VPC |
Select the VPC to which the route table belongs.
If a VPC contains an Elastic Compute Service (ECS) instance that belongs to one of
the following instance families, you cannot create a custom route table for the VPC.
ecs.c1, ecs.c2, ecs.c4, ecs.ce4, ecs.cm4, ecs.d1, ecs.e3, ecs.e4, ecs.ga1, ecs.gn4,
ecs.gn5, ecs.i1, ecs.m1, ecs.m2, ecs.mn4, ecs.n1, ecs.n2, ecs.n4, ecs.s1, ecs.s2,
ecs.s3, ecs.se1, ecs.sn1, ecs.sn2, ecs.t1, and ecs.xn4.
To create a custom route table, you must upgrade or release ECS instances that do
not support advanced VPC features.
Note If your VPC contains ECS instances of the preceding instance families and a custom
route table is created, you must upgrade or release the instance. Otherwise, the custom
route table cannot work as expected. For more information, see Overview of VPC advanced features.
|
Name |
Enter a name for the route table.
The name must be 2 to 128 characters in length, and can contain digits, underscores
(_), and hyphens (-). It must start with a letter.
|
Description |
Enter a description for the route table.
The description must be 2 to 256 characters in length and cannot start with http:// or https:// .
|
After you create custom route tables, you can go to the
Route Tables page to view route tables whose
Route Table Type is
Custom.The following system route entries are automatically added to custom route tables:
- A route destined for the CIDR block 100.64.0.0/10. This route is used for communication
between cloud resources within the VPC.
- A route destined for the CIDR block of a vSwitch of the VPC to which the route table
belongs. This route is used for communication between cloud resources within the vSwitch.
For example, you have created two vSwitches whose CIDR blocks are 192.168.1.0/24 and
192.168.0.0/24. These vSwitches are deployed in the VPC whose CIDR block is 192.168.0.0/16.
Custom route tables that you create for the VPC include the following route entries:
Destination CIDR block |
Next hop |
Type |
100.64.0.0/10 |
- |
System route |
192.168.1.0/24 |
- |
System route |
192.168.0.0/24 |
- |
System route |
Step 2: Add subnet routes
Step 3: Associate the custom route table with a vSwitch
You can associate the custom route table with a vSwitch to manage the routes of the
vSwitch. Each vSwitch can be associated with only one system route table or one custom
route table. Perform the following operations to associate the custom route table
with a vSwitch.
- Log on to the VPC console.
- In the left-side navigation pane, click Route Tables.
- In the top navigation bar, select the region to which the route table belongs.
- On the Route Tables page, find the route table and click its ID.
- In the Route Table Details section, click the Associated vSwitch tab and click Associate vSwitch.
- On the Associate vSwitch page, select the vSwitch that you want to associate and click OK.