Transit routers support route advertisement. You can advertise the routes of a virtual private cloud (VPC) to the transit router to which the VPC is connected. Other network instances connected to the transit router can learn the advertised routes if no route conflict exists.
Background information
The following table lists the default status of VPC routes of different types on a transit router and whether you can advertise or withdraw the routes.
Route type | Network instance | Advertised to a transit router by default | Supports advertisement and withdrawal |
Routes that point to Elastic Compute Service (ECS) instances | VPC | No | Yes |
Routes that point to VPN gateways | VPC | No | Yes |
Routes that point to high-availability virtual IP addresses (HAVIPs) | VPC | No | Yes |
Routes that point to router interfaces | VPC | No | Yes |
Routes that point to elastic network interfaces (ENIs) | VPC | No | Yes |
Routes that point to IPv6 gateways | VPC | No | Yes |
Routes that point to NAT gateways | VPC | No | Yes |
Routes that point to transit routers | VPC | No | No |
System routes of VPCs | VPC | Yes | Yes |
By default, Cloud Connect Network (CCN) instances and virtual border routers (VBRs) advertise routes to the transit router to which they are connected. You cannot advertise or withdraw the routes of a CCN instance or a VBR.
Advertise routes to a transit router
Log on to the CEN console.
On the Instances page, click the ID of the CEN instance that you want to manage.
Go to the tab and click the ID of the transit router that you want to manage.
On the transit router details page, click the Network Routes tab.
On the Network Routes tab, select the network instance and the route table that you want to manage, find the route that you want to advertise, and then click Publish in the Publishing Progress column.
In the PublishRoute message, confirm the information and click OK.
Withdraw routes from a transit router
Log on to the CEN console.
On the Instances page, click the ID of the CEN instance that you want to manage.
Go to the tab and click the ID of the transit router that you want to manage.
On the transit router details page, click the Network Routes tab.
On the Network Routes tab, select the network instance and the route table that you want to manage, find the route that you want to withdraw, and then click Withdraw in the Publishing Progress column.
In the Withdraw Route message, confirm the information and click OK.