If you have deployed ECSs and other cloud services in a VPC, you can configure private zones for the ECSs so that they can communicate with each other or access the cloud services over a private network.
The following are operations for you to create a private zone and add an A record set for it.
Figure 1 shows the process of configuring a private zone for an ECS.
Figure 1 Configuring a private zone for an ECS

To ensure that a private zone and its record sets are properly applied within a VPC, verify that the VPC subnets use the private DNS server addresses provided by the DNS service.
You can also change the DNS servers of the VPC subnet where the domain name is used.
Before using a private domain name (for example, example.com) to access an ECS, you need to create a private zone.
The Private Zones page is displayed.
in the upper left corner and select the desired region and project.You can view the created private zone in the private zone list. You can click the domain name to view SOA and NS record sets automatically added to the zone.
Add an A record set for the created private zone.
The Record Sets tab is displayed.
Retain the default values for other parameters. For details, see Adding an A Record Set.
The added record set is in the Normal state.
To ensure that a private zone and its record sets are properly applied within a VPC, verify that the VPC subnets use the private DNS server addresses provided by the DNS service.
If the DNS server addresses used by VPC subnets are different from those provided by the DNS service, change them.
The Private Zones page is displayed. View the private DNS server addresses for the VPC subnet on the top of the record set list.
in the upper left corner and select the desired region and project.
On the VPC console, change the DNS server addresses for the VPC subnet.
For details, see the Virtual Private Cloud User Guide.